https://wiki.pscs.co.uk/ 2026-05-06T07:03:41+00:00 https://wiki.pscs.co.uk/ https://wiki.pscs.co.uk/_media/wiki:dokuwiki.svg text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:creating_extra_smtp_services?rev=1542192349&do=diff Creating Extra SMTP Services In VPOP3 Enterprise (not VPOP3 Basic) you can create multiple SMTP services. This can be useful if you want VPOP3 to listen on different ports and/or have different settings. There are two ways of doing this. Have a single SMTP service listening on multiple ports or IP addresses text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:incoming_smtp_feed?rev=1542192349&do=diff Incoming SMTP Feed An incoming SMTP feed is where incoming mail is sent directly to your mail server without going through your ISP's POP3 mail server on the way. Advantages An incoming SMTP feed has several advantages over going via a POP3 mailbox: text/html 2025-05-21T07:57:18+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:allowing_mail_relay_through_vpop3?rev=1747814238&do=diff How To Allow Mail Relay Through VPOP3 If you are allowing remote access into VPOP3 to collect mail then you may also want those remote users to be able to send their outgoing mail through VPOP3 as well. This is more complex than allowing users to collect mail, because, by default, SMTP connections are not authenticated. This means that when someone tries to send a message through VPOP3, VPOP3 doesn't know who that user is. This can cause a problem if unauthorised users try to send mail through… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:smtp_rule_example_-_restrict_who_can_send_to_a_local_email_address?rev=1542192349&do=diff SMTP Rule Example - restrict who can send to a local email address If you have a local email address (a user, group or distribution list) and you want to restrict which email addresses can send messages to this address, you can use SMTP rules. There are a few ways you can configure the SMTP rules for this scenario. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:sending_mail_through_your_gmail_account?rev=1542192349&do=diff Sending mail through your Gmail account According to Google, the settings for sending mail through Gmail are: Outgoing Mail (SMTP) Server - requires TLS or SSL: smtp.gmail.com (use authentication) Use Authentication: Yes Port for TLS/STARTTLS: 587 Port for SSL: 465 text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:encrypt_sessions?rev=1542192349&do=diff How To Encrypt Sessions VPOP3 Enterprise 2.6 and later supports SSL/STARTTLS encrypted sessions to VPOP3 itself. So, the email client or web browser will encrypt the data passed to VPOP3 so it cannot be intercepted. This requires an SSL Certificate to be created for VPOP3. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:exchange_2003?rev=1542192349&do=diff Setting up VPOP3 to work with Exchange 2003 The instructions below are for Exchange Server 2003. For other versions of Exchange see here. You can link VPOP3 to Exchange Server, so that Exchange Server sends outgoing mail through VPOP3 and VPOP3 sends any incoming mail directly to Exchange Server. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:error_sending_message_after_authentication?rev=1542192349&do=diff "Error Sending Message After Authentication" in Webmail If you get an error while sending a message using Webmail, such as “Error sending message after authentication - error 0 - text 502 Error: command not implemented” this means that you have another SMTP server running on the VPOP3 computer, and when the VPOP3 Webmail service tries to send the message it is sending it to this other SMTP server, rather than to the VPOP3 server. The Webmail service uses internal commands which the other SMTP… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:configure_a_router_to_allow_incoming_smtp?rev=1542192349&do=diff Accepting Incoming SMTP through a router If your ISP is providing you with an SMTP mail feed (incoming SMTP) and you have VPOP3 connecting to the ISP through a router then you will probably need to modify the router configuration to allow this. Most routers' default configuration will only allow outbound connections (ie connections from the local network out to the Internet). If you need to accept incoming SMTP mail, then you need to tell the router to allow inbound connections on port 25 for … text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:installation_conflicts?rev=1542192349&do=diff Installation conficts During installation, the installer program does some basic checks for conflicting software. This is software which is providing the same services as the VPOP3 software - i.e. SMTP, POP3 and/or LDAP services. For POP3/SMTP it will show the text which the conflicting software announces itself as. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:smtp_rules?rev=1542192349&do=diff SMTP Rules Download rules are applied to messages which arrive at VPOP3 using SMTP - either locally sent messages, or incoming messages received through an SMTP mail feed. To configure the rules, go to the VPOP3 settings, then Services -> SMTP Service text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:limit_size_of_sent_mail?rev=1542192349&do=diff How to limit size of sent mail There are several ways to limit the size of mail which can be sent * Limit the size of mail accepted by the SMTP component of VPOP3 * Limit the size sent for a particular user * Limit size based on 'rules' * Limit size based on text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:require_smtp_authentication?rev=1542192349&do=diff Require SMTP Authentication There are some situations where VPOP3 needs to know who is sending mail. This may be if you have VPOP3 configured to behave differently depending on who is sending messages - eg if you have different message size limits depending on the sender, or if you have message monitoring configured for certain users, or you don't want certain people to be able to send mail at all. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:your_connection_has_been_blocked_temporarily_-_try_again_later?rev=1542192349&do=diff Error message: Your connection has been blocked temporarily - Try again later If you get an error message in your email client software saying Your connection has been blocked temporarily - Try again later or Server access temporarily blocked! Please try again later text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:550_5.7.1_unable_to_relay_for?rev=1542192349&do=diff 550 5.7.1 Unable to Relay for... When trying to send emails from your email client software you get an error in your email client 550 5.7.1 Unable to relay for ... This error is happening because you have installed the Microsoft IIS SMTP Service, and your email client is talking to that service rather than to VPOP3. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:exchange_2007?rev=1542192349&do=diff Exchange 2007 You can link VPOP3 to Exchange Server, so that Exchange Server sends outgoing mail through VPOP3 and VPOP3 sends any incoming mail directly to Exchange Server. You should first of all set up VPOP3 to send and receive Internet email as normal. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:isp_needs_ssl_connection?rev=1542192349&do=diff ISP needs SSL connection A few ISPs use a non-standard and not recommended system of encrypting connections to their SMTP mail servers. These generally are called 'SSL' connections and work on an alternate port other than the standard SMTP port 25. (The correct way to encrypt connections is to use a system called TLS which works on the standard SMTP port). text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:smtp_client_problem?rev=1542192349&do=diff VPOP3 - SMTP Client Problem These errors occur whilst VPOP3 is communicating with your ISP's SMTP mail server to send your mail. If the message text is: Error with SMTP Client (XXXX (YY)) The server connection was closed unexpectedly Then this means that the the connection between VPOP3 and your ISP's SMTP mail server was closed when VPOP3 did not expect it to be. This can be caused by the network connection failing or a bug in the ISP's mail server which drops the connection in abnormal circ… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:using_vpop3_with_microsoft_exchange?rev=1542192349&do=diff Using VPOP3 with Microsoft Exchange Server You can link VPOP3 to Exchange Server, so that Exchange Server sends outgoing mail through VPOP3 and VPOP3 sends any incoming mail directly to Exchange Server. You should first of all set up VPOP3 to send and receive Internet email as described in the online help. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:vpop3_sending_high_volumes_of_unrecognised_mails?rev=1542192349&do=diff SMTP Relay Protection in VPOP3 SMTP Relay Protection should be used on ALL SMTP mail servers (such as VPOP3) which have a permanent connection to the Internet. You may also want to use it on servers which are only connected occasionally via a dial-up connection. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:550_not_permitted?rev=1542192349&do=diff 550/553 Not Permitted error from BT Internet's mail servers BT Internet's mail servers only allow messages to be sent from 'approved' email addresses. If you try to send messages from other addresses BT's mail servers may return a '550 Not Permitted' error, a '553' error, or may silently discard the message depending on what their server feels like doing today. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:isp_needs_smtp_authentication?rev=1542192349&do=diff The ISP needs SMTP Authentication If your ISP needs you to use SMTP authentication when sending mail to them, then you just need to tell VPOP3 to use authentication when sending. Click the Mail Connectors button at the top of the page, then click on the relevant text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:isp_needs_you_to_connect_on_port_587?rev=1542192349&do=diff ISP needs you to connect on port 587 Some ISPs will need you to send mail using port 587, instead of port 25. Port 587 is the 'SMTP Submission' port which is commonly used instead of, or as well as, the standard SMTP port 25 for when users are sending mail to a smart host/relay server. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:obtaining_error_logs?rev=1542192349&do=diff How to Obtain Error Logs As part of diagnosing a support issue our support team may ask you to send them various log files. This page explains how to obtain the right files at the right time. How Logging Works Under its default settings VPOP3 logs a minimal amount of information about what it is doing to various files in the main VPOP3 directory. When investigating a support issue it is often the case that we will need you to switch on logging to extra files or increase the level of detail be… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outlook_2007?rev=1542192349&do=diff How to configure Outlook 2007 Email SMTP Authentication To set up SMTP authentication in Outlook 2007, if your VPOP3 requires it, go to Tools -> Account Settings, select your email account and press Change.... Then, press the More Settings... button text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outlook_2010?rev=1542192349&do=diff How to configure Outlook 2010 In many ways, configuring Outlook 2010 is a similar to configuring Outlook 2007. The biggest difference you are likely to notice is the new “Ribbon” interface, in place of the traditional menu bar (File, Edit, View, etc.) Email text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:seeing_where_a_message_came_from?rev=1542192349&do=diff Seeing where a message came from Sometimes you need to check to see where a message really came from. The 'From:' email address is easily forged, so that cannot be relied upon. The first thing you have to do is to get the full message headers. These may look daunting, but are very useful for problem diagnosis. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:using_vpop3_spam_filtering_with_lan_forwarding?rev=1542192349&do=diff Using VPOP3 Spam Filtering with LAN Forwarding When using the VPOP3 Spam filter with LAN forwarding you need to be aware a bit of how it works. The spam filter will only quarantine messages which are going to a VPOP3 user. This is because that user needs to be able to log into VPOP3 to be able to view their quarantined messages. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:550_5.7.1_recipient_prohibited_x?rev=1542192349&do=diff 550 5.7.1 Recipient Prohibited (x) (where 'x' is a number) This means that you have an SMTP rule which is rejecting this recipient. The (x) indicates the SMTP rule number which is causing the rejection. View & edit your SMTP rules at Services -> SMTP Server text/html 2025-08-18T15:28:11+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:configure_srs?rev=1755530891&do=diff Configure SRS In VPOP3 8.8 and later, you can use Lua scripting to implement 'SRS' (Sender Rewriting Scheme') in VPOP3 This involves adding a couple of functions to rewrite outgoing return paths in 'relayout.lua' or 'mxout.lua' as appropriate and a couple of functions to redirect rewritten bounce message recipients in 'smtpsvr.lua' text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:custom_filtering_incoming_mail?rev=1542192349&do=diff Custom filtering incoming mail If you want to filter incoming mail using custom rules there are a few ways of doing this, depending on your exact requirements. * Download rules - if your incoming mail is via POP3 collection, you want to filter on headers, size etc (not contents) text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:forwarded_emails_not_arriving?rev=1542192349&do=diff Forwarded Emails Not Arriving If you are having problems having VPOP3 forward incoming messages to an external address, but sending messages directly to that address works OK, and forwarding internal messages to that address works OK, then the problem may be the SMTP return address which VPOP3 is using. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:isp_needs_pop3_before_smtp_authentication?rev=1542192349&do=diff The ISP needs POP3 before SMTP authentication Some ISPs (especially in Germany) require you to log on to collect your POP3 mail before they will allow you to send any mail through their SMTP relay servers. VPOP3 actually connects to the POP3 server and SMTP server at the same time, so usually it will not have successfully logged onto the ISP's POP3 server before it tries to start sending mail. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:smtp_client_connection_problem?rev=1542192349&do=diff VPOP3 - SMTP Client Connection Problem These errors occur during the period when VPOP3 is trying to establish a connection to your ISP's SMTP mail server to send outgoing mail. They can mean that you have entered the SMTP Server address incorrectly, or that there is a problem with the network, or that your ISP's mail server is not working properly. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:spam_filter_not_working?rev=1542192349&do=diff Spam filter not working If the VPOP3 spam filter appears not to be working at all, the first thing to do is to look at the message headers of an incoming message to see if the spam filter is being run at all. Check to see if a header line beginning with X-VPOP3-Spam text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:data_stream_contained_nul_character?rev=1542192349&do=diff Data stream contained NUL character Description of the problem NUL characters (bytes with value 0) are not allowed in email messages and should not be transmitted over POP3, SMTP or IMAP4 except in certain circumstances. If an attachment contains such a byte it must be encoded using text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:error_message_after_sending_rcptto_-_error_0_-_text_550_5.7.1_relaying_not_allowed_bad_sender_ip_address?rev=1542192349&do=diff Error message after sending RCPTTO: - error 0 - text 550 5.7.1 Relaying not allowed! Bad sender IP address If you get this error message from within Webmail, then it usually means that the SMTP service access restrictions are blocking Webmail from sending mail. text/html 2025-10-06T15:21:37+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:error_messages?rev=1759764097&do=diff Error Messages This is the place to look if you are trying to trouble shoot a problem and you have received or have access to a specific error message or error code. If instead your problem is that something you think is set up correctly is not working then the best place to look would be the text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:out_of_disk_space_when_sending_mail?rev=1542192349&do=diff Out of Disk Space When Sending Mail The first thing you should do is check that there is enough free disk space on the disk where VPOP3 is installed. VPOP3 requires a certain amount of free space before it will allow new messages to be sent, so the disk might not be totally full, but VPOP3 will still report that there is insufficient disk space when you try to send a new message. This buffer zone is designed to help prevent the disk totally filling up, which can cause lots of bigger problems! text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outbound_messages_not_appearing_in_monitor?rev=1542192349&do=diff Outbound Messages Not Appearing in Monitor Target Mailbox For VPOP3 to monitor outbound messages it needs to be able to work out that the message is FROM: a user whose mail should be monitored. To do this it has to examine the FROM: address in the message header. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outgoing_mail?rev=1542192349&do=diff Outgoing Mail * Create a Mail Sender * Route MX Sent (Direct) Outbound Mail Through Your ISP's Relay Server * ISP needs SSL connection * ISP needs you to connect on port 587 * ISP needs SMTP Authentication * ISP Needs POP3 Before SMTP Authentication * Limit size of sent mail * Require SMTP Authentication when users send mail to VPOP3 * Sending different users' mail through different ISP relay accounts * Restricting number of messages sent (per hour etc) * Restricting numbe… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:problems_sending_messages_to_spam_your_domain?rev=1542192349&do=diff Problems sending messages to spam@<your domain> If a VPOP3 user forwards a message to spam@<your domain>, then the VPOP3 spam filter will train itself that that message was spam. If, when you forward the message, you get an error message like: Subject: Mail Delivery Failure Delivery Failure Report. The following message was incorrectly addressed. Recipient: "spam" is unrecognised. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:rbl_checking_not_working_in_vpop3_enterprise?rev=1542192349&do=diff RBL Checking not working in VPOP3 Enterprise VPOP3 Enterprise has an RBL checking feature which is configured in the VPOP3 Settings at Services -> SMTP Server -> SPAM Reduction -> Realtime Blacklist Rules If it does not seem to be working properly, there are a few reasons why the RBL feature may not work. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:use_the_vpop3_status_monitor?rev=1542192349&do=diff How to use the VPOP3 Status Monitor The VPOP3 Status Monitor is a small program which displays a postbox icon (usually red) in the Windows notification area (usually at the bottom right of the screen - by the clock). This icon can be used for quick access to various VPOP3 facilities. Note that the Status Monitor is text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:vpop3_access_security?rev=1542192349&do=diff How To Setup VPOP3 Service Security VPOP3 can be configured to restrict access to its various services depending on the client computer's IP address. This is useful if you want to allow access from only certain IP addresses (eg within your LAN) and prevent access from other IP addresses (eg the Internet). text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:421_4.3.2_vpop3_too_many_connections_from_your_ip_address_-_try_later?rev=1542192349&do=diff 421 4.3.2 VPOP3 Too many connections from your IP address - try later If you see this error message when you are sending messages, then it means that VPOP3 has detected too many simultaneous connections from your IP address. This would usually happen if the sender is another mail server as they can make many simultaneous connections when there are lots of messages to send. The error code that VPOP3 gives means that the sender should try sending the messages later, so it should be possible to e… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:450_4.3.2_content_filter_timeout?rev=1542192349&do=diff 450 4.3.2 Content Filter Timeout If you get this error appearing when messages are sent to VPOP3, either in a bounce message, or in the VPOP3 status monitor, it means that the VPOP3 computer filter is taking more than the allowed amount of time (usually 60 seconds). text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:535_authentication_failed?rev=1542192349&do=diff 535 Authentication Failed This is an SMTP error meaning that an attempt to authenticate has failed. If this error is appearing when the email client is trying to log into VPOP3, then you can check the VPOP3 'SECURITY.LOG' file which may contain more information, such as an invalid password, unknown username, etc. (This information is not returned in the SMTP session because it would help an attacker). text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:550_5.7.1_relaying_not_allowed_bad_sender_ip_address?rev=1542192349&do=diff 550 5.7.1 Relaying not allowed! Bad sender IP address This SMTP error message means that the computer which is sending the message is not permitted to send outgoing messages based on the VPOP3 SMTP Service's Access Restrictions. This is probably because someone is trying to send messages from outside your local network, and you have not configured VPOP3 to allow this. You have to be careful when allowing this, because you may configure VPOP3 to be an open-relay, which is a text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:allow_remote_access_to_vpop3_mailboxes?rev=1542192349&do=diff Allow Remote Access to VPOP3 Mailboxes Sometimes people want to be able to access their office VPOP3 mail server from a remote site or mobile phone etc. These instructions assume you have a permanent Internet connection (eg ADSL, Cable etc). If you don't have a permanent Internet connection, see text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:database_size?rev=1542192349&do=diff VPOP3 Database Size The VPOP3 directory is stored in the VPOP3\pgsql\data folder and subfolders. If you are concerned about the size of the VPOP3 database, there are several factors which may make the database larger than you would expect: * The VPOP3 database contains a lot more information than just messages in mailboxes. This can include settings, outgoing messages, historical logging information, statistical information for the spamfilter, information about archived messages, etc. Also,… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:invalid_helo_name?rev=1542192349&do=diff SMTP error 'Invalid HELO name' When sending mail you may get an error from the remote SMTP server saying something like 'Invalid HELO name' This happens if the host name configured in VPOP3 does not look like a valid Internet host name (e.g. 'mail.domain.com'). Some SMTP servers don't bother checking this value because it has no authentication value at all, but a few do check that it looks correct. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:route_mx_sent_direct_outbound_mail_through_your_isp_s_relay_server?rev=1542192349&do=diff Route MX Sent (Direct) Outbound Mail Through Your ISP Some mail providers (for example Hotmail, AOL and GMail) will reject mail sent from servers running on dynamic IP addresses. It is possible to route such mail through your ISP's relay server whilst still sending most mail direct to the recipient server using MX text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:troubleshooting_tips?rev=1542192349&do=diff Troubleshooting Tips Telnet One of the most basic, and useful, tools for troubleshooting email systems is a Telnet client. Installing Telnet Client Unfortunately, since Windows XP, Microsoft do not install the Telnet client into Windows by default, so you may need to install the Telnet client yourself. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:use_download_rules_for_incoming_pop3_filtering?rev=1542192349&do=diff Use Download Rules for incoming POP3 message filtering If you have VPOP3 retrieving messages from a POP3 account on an ISP, then you can use Download Rules to do basic filtering on incoming messages. (If you have incoming SMTP, then use SMTP Rules instead) Download rules cannot perform all mail filtering tasks. For more features, text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:552_5.2.3_message_too_large_-_contact_your_administrator?rev=1542192349&do=diff 552 5.2.3 Message too large - contact your administrator Or 552 5.2.3 Message exceeds fixed maximum message size If this error message is coming from VPOP3 when you are sending a message, it means that the message you are sending is prohibited by your VPOP3 settings. There are two places where the size limit could be set. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:11001?rev=1542192349&do=diff Socket Error 11001 - Host not found (authoritative answer) This means that the ISP POP3 or SMTP server which you have told VPOP3 to connect to does not currently exist. This might be that you have mistyped the server address, or that your ISP is having temporary problems, or that you are using an internal text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:backscatter?rev=1542192349&do=diff Backscatter In email, “backscatter” is the term used if you send bounce messages back to spam messages. As most spam messages use forged email addresses, then the bounce messages will go to an innocent person, who will find them very annoying. Stopping VPOP3 from sending Backscatter text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:changing_a_user_s_password?rev=1542192349&do=diff Changing a user's password To change a user's password in VPOP3, you should log into the VPOP3 settings, go to the 'Users' page, then double-click on the user whose password you want to change. This will bring up a window giving you access to the user's settings. Go to the 'Passwords' tab where you can set the passwords. text/html 2026-03-18T20:20:50+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:how_to?rev=1773865250&do=diff "How To" Articles Installation/Upgrades * Download VPOP3 * Install VPOP3 * Move VPOP3 * Upgrade VPOP3 * Upgrade VPOP3 to version 5.x or 6.x from version 4 or earlier * Upgrade VPOP3 to version 7.x from version 6 or earlier * Upgrade VPOP3 to version 8.x from version 7 or earlier * Upgrade VPOP3 to version 9 or later from version 7 or 8 * Performance Requirements * Installation Checklist General Configuration * Initial Configuration * Users * Add an Alias * Create… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:mozilla_thunderbird?rev=1542192349&do=diff How to configure Mozilla Thunderbird This article won't show you all the possible settings in Thunderbird, because there are so many. Thunderbird is one of the most powerful & flexible email clients available at the time of writing, especially if you use IMAP4 (with VPOP3 Enterprise). text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outlook_outlook_express_are_sending_mail_repeatedly?rev=1542192349&do=diff Outlook / Outlook Express is sending mail repeatedly If you are using Outlook or Outlook Express you may occasionally find that mail is being sent repeatedly. There are a couple of possible reasons for this which we know of Sending taking too long text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:sender_domain_must_resolve?rev=1542192349&do=diff Sender Domain Must Resolve If you receive an 'SMTP Client Error' something like: 451 (user@domain.com) Sender Domain Must Resolve this means that the ISP's mail server cannot find the domain.com part of the email address. Often this means that the FROM address of the message is invalid, or that the text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:sender_policy_framework?rev=1542192349&do=diff Sender Policy Framework / SPF SPF is a system used to tell mail servers which IP addresses can send mail from which domains. It is designed to reduce 'spoofing' of email addresses. For instance, if you receive an email message from your bank, your mail software can check that it came from an IP address authorised to send mail from your bank, and treat the message with suspicion if it didn't come from an authorised IP address. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:421_4.3.2_vpop3_smtp_server_access_disabled_-_content_scanner_problem?rev=1542192349&do=diff 421 4.3.2 VPOP3 SMTP Server access disabled - content scanner problem! This usually happens if the “VPOP3 AV” virus scanner has a problem it can't automatically recover from. This may be a fatal error, or a licencing issue. You can check this on the Settings text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:421_4.3.2_vpop3_smtp_server_access_disabled_-_low_memory?rev=1542192349&do=diff 421 4.3.2 VPOP3 SMTP Server access disabled - low memory! This error means that VPOP3 has detected that there is not enough free memory available on the server. If this happens it refuses to accept new messages because that may make the PC crash and possibly lose data. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:10053?rev=1542192349&do=diff Socket Error 10053 - An established connection was aborted by the software in your host machine. Error 10053 means that an established connection has been dropped. There are three descriptions of this error message we know about, but the descriptions are given by Windows, so they may vary depending on your version of Windows: text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:10060?rev=1542192349&do=diff Socket Error 10060 - Operation Timed Out This error is quite self explanatory. It means that Windows reported that a connection attempt or idle connection timed out. If this error occurs during a connection attempt (eg in a VPOP3 - SMTP Client connection problem error message), then it means that Windows couldn't connect to the ISP mail server within a fixed time (the timeout limit is fixed within Windows itself). This problem can either mean that your ISP is having a problem, that you are con… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:10061?rev=1542192349&do=diff Socket Error 10061 - The attempt to connect was forcefully rejected Error 10061 means that the computer which VPOP3 was trying to connect to (probably at your ISP) refused the connection from the computer running VPOP3. There are several possibilities that can cause error 10061: text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:compatibility_with_spampal?rev=1542192349&do=diff Compatibility with SpamPal Some users have reported a problem installing/running the PostgreSQL component when the 'SpamPal SMTP Transparent Feature' is enabled. Disabling this feature has resolved the problem for these users. Unfortunately we don't have further information on this, as we don't use SpamPal ourselves, but the above information may be useful if you have this problem. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:controlling_vpop3_via_email?rev=1542192349&do=diff Controlling VPOP3 via Email You can control certain aspects of VPOP3 by sending emails to 'mailer_daemon@<your domain>' The subject line must be one of the lines below: * Set Assistant * Query Assistant * Password * Set Forwarding * Query Forwarding text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:copy_outgoing_mail?rev=1542192349&do=diff Copy Outgoing mail Sometimes people need to copy outgoing mail for various reasons. There are several ways of doing this in VPOP3 depending on your exact requirements: * Message Monitoring - this copies all outgoing, incoming and/or internal mail sent by/to specific users to another specific user text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:create_a_mail_collector?rev=1542192349&do=diff * Configure a Router to Allow Incoming SMTP text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:encore_32_estate_agent_software?rev=1542192349&do=diff How to configure Encore 32 Estate Agent Software * Close down the Encore software * Open up the “Maintenance 32” program * Click on “Email Configuration” * Enter the IP address of the VPOP3 computer into the “SMTP Server address” text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:french_webmail_language_file?rev=1542192349&do=diff French Webmail Language File Copy/paste the text below to a file 'french.lng' or 'francais.lng' in the VPOP3 directory. (French users, feel free to update/correct the text below) #login page logintitle=VPOP3 Login webadminlogin=web admin login webmaillogin=web mail login enterusername=You must specify your VPOP3 username here bookmarksnotsupported=I'm sorry, but your web browser does not support this function. You will have to add this page to your bookmarks manually. loginfailed=Login Faile… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:german_webmail_language_file?rev=1542192349&do=diff German Webmail Language Page Copy/paste the text below to a file 'german.lng' in the VPOP3 directory. (German users, feel free to update/correct the text below) #login page logintitle=VPOP3 Login webadminlogin=web admin login webmaillogin=Webmail Anmeldung enterusername=Sie m&uuml;ssen einen Benutzernamen angeben bookmarksnotsupported=I'm sorry, but your web browser does not support this function. You will have to add this page to your bookmarks manually. loginfailed=Anmeldung fehlgeschlagen … text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:handling_mail_for_multiple_incoming_domains?rev=1542192349&do=diff Handling mail for multiple incoming domains VPOP3 can easily handle mail for several incoming domains. Exactly how you do it depends on the exact situation. All domains are 'aliases' If the domains are aliases of each other, for instance, you have 'mycompany.com' and 'mycompany.org', both of which are the same, so each address at mycompany.com also exists at mycompany.org, and the emails go to the same people regardless of which domain is used, then you simply configure the domains in the ma… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:iphone?rev=1542192349&do=diff Setting up an iPhone/iPad/iPod Touch To set up an iPhone to access VPOP3's mail, you first of all need to configure VPOP3 to allow access by remote users (unless you will only be using the iPhone in the office, connected via WiFi to the office LAN). Adding the mail account to your iPhone/iPad text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:no_transport_provider_is_available?rev=1542192349&do=diff Outlook/Windows Messaging reports "No transport provider is available" If Outlook or Windows Messaging reports No transport provider is available when trying to connect to VPOP3, it can mean several things. (This must be a contender for “the world's most meaningless error message text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:problems_sending_mail_via_bt_from_your_own_domain?rev=1542192349&do=diff Problems sending mail via BT from your own domain BT Internet only allow you to send mail through their mail servers from your BT Internet address or other registered address. Attempts to send from other addresses will give you a 553 SMTP error message. text/html 2020-07-22T10:32:40+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:signing_outgoing_mail_with_dkim?rev=1595413960&do=diff Signing outgoing mail with DKIM DKIM, also known as DomainKeys Identified Mail, is a form of email authentication that digitally signs emails to prove that they were sent from authorized domains and aren't fake emails. Companies like Google and Yahoo use DKIM to sign their emails and it is becoming ever more popular. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:spanish_webmail_language_file?rev=1542192349&do=diff Spanish Webmail Language File Copy/paste the text below to a file 'spanish.lng' or 'espanol.lng' in the VPOP3 directory. (Spanish users, feel free to update/correct the text below) #login page logintitle=VPOP3 Login webadminlogin=web admin login webmaillogin=web mail login enterusername=Especificar aca el usuario de Correo bookmarksnotsupported=Disculpe, pero su navegador no soporta esta funcion. loginfailed=Login Fallido - Favor reintente nuevamente invalidlogin=Detalles del login inválidos… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:timeout_problems_when_sending_or_receiving_attachments?rev=1542192349&do=diff Timeout problems downloading/uploading messages with attachments There are various possible reasons for this, usually to do with third party internet security software but they may also be associated with Windows TCP/IP or dial-up adapter issues. You may not have problems with other software, but that doesn't mean the problem is being caused by VPOP3. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:using_advanced_vpop3_features_with_lan_forwarding?rev=1542192349&do=diff Using VPOP3 Advanced Features with LAN Forwarding If you are wanting to use any of VPOP3's advanced features (such as mailing lists, message monitoring, wildcard aliases etc) because you are LAN forwarding to a less capable server, then you will usually need to have VPOP3 do all its normal message routing functions initially, then, as the final stage have it forward the messages on to the other server. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:vpop3_xxxxx_server_access_not_allowed?rev=1542192349&do=diff VPOP3 Server Access Not Allowed If you get an error like: -ERR VPOP3 Server access not allowed! when trying to access VPOP3, then this means that the relevant server's IP Access Restrictions defined in VPOP3 do not allow access from your client computer. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:vpop3_xxxxx_server_access_not_allowed_-_see_your_administrator?rev=1542192349&do=diff Error Message - VPOP3 xxxx Server Access Not Allowed - See Your Administrator If you get an error message when trying to connect to the VPOP3 SMTP/POP3/IMAP4/etc service which says VPOP3 xxxx Server Access not allowed - See your administrator (where xxxx is replaced with the specific service name, and there may be protocol specific error codes before the message)