PSCS Wiki

VPOP3 - POP3 Client Problem

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 - POP3 Client Problem These errors occur whilst VPOP3 is communicating with your ISP's POP3 mail server to retrieve your mail. The server connection was closed unexpectedly If the message text is Error with Pop3 Client (XXXX (YY)) The server connection was closed unexpectedly

VPOP3 - SMTP Client Problem

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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…

How to use the VPOP3 Status Monitor

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

How To Setup VPOP3 Service Security

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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).

Socket Error 10060 - Operation Timed Out

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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…

How To Allow Mail Relay Through VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2025-05-21T07:57:18+00:00

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…

-ERR Unknown User

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

-ERR Unknown User -ERR Unknown User is a POP3 error. There are two places you can receive it: * If you receive it as part of a 'POP3 Client Error' email message from VPOP3, then it means that VPOP3 was unable to log on to your ISP's mail server because the ISP POP3 server reported an error

Error Message Handling

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Error Message Handling VPOP3 will normally send an error message to the Main Administrator every time it encounters an error. We recommend you leave it like this in most cases - if an error message occurs repeatedly, then it usually means there's an underlying problem which needs resolving rather than ignoring.

Problems accessing VPOP3 Settings

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Problems accessing VPOP3 Settings If you have problems accessing the VPOP3 settings: * Go to Start -> Programs -> VPOP3 -> Configure VPOP3 on the VPOP3 computer. That should open up a web browser and take you to the login page * If VPOP3 doesn't show the login page, and shows a '403' error page instead, that means that the access restrictions for the WebMail service have been restricted so that this computer cannot access the WebMail service.

Move VPOP3 Version 3 or 4 to a new PC

Anonymous (anonymous@undisclosed.example.com) — 2019-11-12T16:09:08+00:00

Move VPOP3 Version 3 or 4 to a new PC Moving VPOP3 Version 3 or 4 to a new PC is slightly different from moving earlier versions, because of the database system. The summary of steps is: * Stop VPOP3 on the original PC * Manually make a backup of the database on the original PC

Spamfilter Whitelist & Blacklist

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Spamfilter Whitelist & Blacklist The VPOP3 spamfilter has a whitelist and a blacklist for sender addresses. It also has a whitelist and blacklist for words/phrases. You can view these lists in the VPOP3 settings by going to Settings -> Spamfilter ->

421 4.3.2 VPOP3 Too many connections from your IP address - try later

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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…

552 5.2.3 Message too large - contact your administrator

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

Socket Error 10053 - An established connection was aborted by the software in your host machine.

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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:

Socket Error 11002 - Host not found (Non-Authoritative answer)

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Socket Error 11002 - Host not found (Non-Authoritative answer) This means that VPOP3 is not getting a response from a DNS server when it is trying to look up the name of the ISP's mail server(s). Usually this means that Windows either does not know the address of a valid

-ERR Can't open the message file - it's gone!

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

-ERR Can't open the message file - it's gone! If VPOP3 receives the error message “-ERR Can't open the message file - it's gone!” from your ISP's POP3 server when it is downloading messages, this is a symptom of a fundamental bug in your ISP's POP3 server.

-ERR Mailbox Locked error

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

-ERR Mailbox Locked error If your email client displays an '-ERR Mailbox Locked' or '-ERR [IN-USE] Mailbox Locked' error when trying to log into VPOP3 it means that the mailbox is locked. The POP3 standard requires that POP3 mailboxes have an 'exclusive lock' on them when they are in use. This means that only one POP3 client can access the mailbox at once. Also, if a POP3 mailbox is currently accessing a mailbox, then no IMAP4, Webmail or administrator access is allowed to the mailbox at the s…

IMAP4 'Ghost Folders'

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

IMAP4 'Ghost Folders' Sometimes your IMAP4 email client may show folders in the folder tree, but when you select them, you get an error that the folder does not exist. This happens because IMAP4 has the concept of being able to 'subscribe' to folders - this means that you can hide folders by unsubscribing from them.

Outlook/Windows Messaging reports "No transport provider is available"

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

Repairing corrupted database

Anonymous (anonymous@undisclosed.example.com) — 2024-01-15T11:35:45+00:00

Repairing corrupted database With PostgreSQL (as with most high-end databases) the database system will automatically recover after power failures etc, if it can. If it can't then there is no manual 'repair' function, because the data cannot totally be recovered (or it would automatically have been recovered).

Sender Domain Must Resolve

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

Status Monitor is open during installation

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Status Monitor is open during installation During installation, if the installer says that the VPOP3 Status Monitor is open, and won't let you install VPOP3, that means that Windows is refusing to let the installer overwrite the VPOP3STATUS.EXE program. Usually that means that it is currently running.

VPOP3 Status Monitor Problems

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 Status Monitor Problems The VPOP3 Status Monitor is the program which shows the little (usually red) postbox icon in the Windows task tray. This usually launches automatically from the Windows startup group. This program is VPOP3Status.EXE on the disk, or can be run manually from

VPOP3 Server Access Not Allowed

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

421 4.3.2 VPOP3 SMTP Server access disabled - low memory!

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

450 4.3.2 Content Filter Timeout

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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).

550 5.7.1 Recipient Prohibited (x)

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

550 5.7.1 Relaying not allowed! Bad sender IP address

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

550/553 Not Permitted error from BT Internet's mail servers

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

Error 1068 - the dependency service or group failed to start

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Error 1068 - the dependency service or group failed to start If you get an error 1068 when you try to start VPOP3, then this usually means that the VPOP3DB service (if you are using VPOP3 v5 and later) did not start. In this case try starting that service manually and see what error message is generated then.

1069 or 7000 Login Failure error when starting VPOP3DB service

Anonymous (anonymous@undisclosed.example.com) — 2019-11-13T15:35:55+00:00

1069 or 7000 Login Failure error when starting VPOP3DB service A 1069 or 7000 login failure error when starting the VPOP3DB service usually means that something is 'wrong' with the vpop3postgres account in Windows - the password may have expired, or someone may have reset the password.

Socket Error 10049 - The specified address is not available from the local computer

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Socket Error 10049 - The specified address is not available from the local computer This error normally means that you have entered an invalid address on the IP Address to Bind To entries on the Services page in the VPOP3 settings. The addresses entered here should be either

Socket Error 10054 - The virtual circuit was reset by the remote end

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Socket Error 10054 - The virtual circuit was reset by the remote end Error 10054 means that the connection between VPOP3 and a remote computer (eg the ISP or another computer on your LAN) was disconnected by something outside of VPOP3. This is often caused by anti-virus software or Internet security/firewall on the VPOP3 machine but it could be any of a number of things. Any software or hardware that is sitting between VPOP3 and the ISP could be the root cause.

Socket Error 10055 - No Buffer Space Available

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Socket Error 10055 - No Buffer Space Available Error 10055 means that Windows has run out of TCP/IP socket buffers because too many connections are open at once. Things to check if this happens are: * Is there any other TCP/IP software running on the same PC as VPOP3 - eg a proxy server

Socket Error 10061 - The attempt to connect was forcefully rejected

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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:

Socket Error 10503 - No More Data

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Socket Error 10503 - No More Data Error 10503 means that the connection between VPOP3 and a remote computer (normally your ISP) was dropped at an unexpected time. This is different from the error 10054 in that this is a controlled line drop. One way this can happen is if the ISP's POP3 server uses an obsolete standard which allows it to drop the connection if a POP3 'LIST' command is performed on an empty mailbox. The current standard requires that the connection is not dropped until the clien…

Socket Error 11001 - Host not found (authoritative answer)

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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

Attachments have been removed or renamed

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Attachments have been removed or renamed If you have received an email and one or more of its attachments have been removed or renamed, it might be a result of Attachment Filtering. You can inspect the filtering rules by going to Administration Settings -> Settings ->

Autoupdate process failed with error code 786432

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Autoupdate process failed with error code 786432 This is actually a success result from the automatic update program, which is incorrectly being identified as an error in VPOP3. This will be fixed in VPOP3 v6.15 In fact, this means that the automatic update program needed to be restarted automatically because it had updated itself. It is not a problem. Future versions of VPOP3 will suppress this error message.

How to Backup VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

How to Backup VPOP3 By default VPOP3 v3 and later will automatically perform a daily backup of the database into a file called DBBACK-x.DMP, where the backup file rotates on a weekly basis (DBBACK-0.DMP is Sunday's backup, DBBACK-1.DMP is Monday's backup, etc).

C++ Error Popup

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

C++ Error Popup If VPOP3 crashes with a C++ error popup window, that means that an 'exception' has been thrown - something unusual has happened, and VPOP3 doesn't know how to recover automatically. Often these are due to database errors. There are two places you can look for the cause of the error:

Configure Email Signatures

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Configure Email Signatures * Global Signatures * Personal Signatures * Webmail Signatures Notes When creating a signature it is generally best to keep it as short as possible. Disclaimers & confidentiality notices in emails are generally regarded as having little or no legal significance, so lengthy signatures just use up bandwidth.

How to create an SSL Certificate

Anonymous (anonymous@undisclosed.example.com) — 2026-03-23T10:18:43+00:00

How to create an SSL Certificate VPOP3 Enterprise supports SSL certificates for encrypted sessions. The basic mechanism to create an SSL certificate is that you have to generate a CSR (Certificate Signing Request) then send that to a CA (Certificate Authority) who will sign your certificate and give you the certificate back.

Daily Summary is not reporting all Sent messages

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Daily Summary is not reporting all Sent messages For VPOP3 to log outbound messages it needs to be able to work out that the message is FROM: a user whose mail is handled by the local VPOP3. To do this it has to examine the FROM: address in the message header.

Database Maintenance

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Database Maintenance VPOP3 uses the PostgreSQL database server for most of its data storage. Normally this will not require any special maintenance, because it will manage itself. To do any special database maintenance you will need to close down VPOP3 first, because PostgreSQL needs exclusive access to the database to perform any operations such as decreasing the size of database files. Note that these operations may take some time! There are some PostgreSQL utility programs in the VPOP3\pgs…

VPOP3 Database Size

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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,…

How to Delete a User

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

How to Delete a User To delete a user from VPOP3, go to Users -> Accounts, select the user you wish to delete, and press the Delete button. Deleting an administrator You cannot delete the user as whom you are currently logged into the VPOP3 settings (e.g.

-ERR Password supplied for "xx" is incorrect

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

-ERR Password supplied for "xx" is incorrect If you receive a 'POP3 Client Error' something like: -ERR Password supplied for “xx” is incorrect this means that the password on the 'In Mail' tab in VPOP3 for the indicated user is entered incorrectly.

Error expanding recipient - Nesting Level too deep

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Error expanding recipient - Nesting Level too deep You receive an error message saying: Error expanding recipient "" Nesting Level too deep (51) Check the configuration for loops (Note the '51' number may be slightly different - that's the nesting level - anything over 50 is detected as an error)

Error message after sending RCPTTO: - error 0 - text 550 5.7.1 Relaying not allowed! Bad sender IP address

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

"Error Sending Message After Authentication" in Webmail

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

"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…

Exceptions

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Exceptions An exception happens if VPOP3 encounters a problem it did not expect. In some cases it can recover automatically, but in other cases that isn't possible. Common causes VPOP3 2.6 and earlier In VPOP3 2.6 and earlier it was quite common for there to be database corruption problems with the SQLite database which was used in those versions.

Full Text Search

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Full Text Search In VPOP3 Enterprise v7.0 a facility for full-text-search on message content was added. Because the full-text-search indexes can be quite big, this facility is optional. For several reasons, the full-text-search is stored in a separate PostgreSQL database. This means that it is not backed up with your standard backups. After a restore, the full-text-search index can be rebuilt from the raw message content.

Using IMAP4 with VPOP3 Enterprise

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Using IMAP4 with VPOP3 Enterprise VPOP3 Enterprise supports IMAP4 email clients (VPOP3 Basic does not). With IMAP4 the email folders and messages are stored on the mail server. The email client then synchronises with the server. Also, unlike with POP3, several things can access the same mailbox at once.

How to install the VPOP3 Status Monitor on other PCs

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

How to install the VPOP3 Status Monitor on other PCs The VPOP3 status monitor icon is run by a separate program from VPOP3, which communicates with VPOP3 using TCP/IP. This means that this program can be installed on any PC which can connect to the VPOP3 computer using TCP/IP (on port 5109 by default).

How to Install VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2021-03-08T10:48:40+00:00

How to Install VPOP3 Simply download VPOP3 from the website, and run the installation program and follow the prompts. Occasionally people may have problems with the PostgreSQL part of the installation. If that happens, please contact us either by email at support@pscs.co.uk or by phone to +44 (0)1484 855800, and we will do our best to help.

Installation checklist

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Installation checklist This list contains some things you may want to check before or after installing VPOP3 to make sure it's not going to encounter any common issues. Before installation * Make sure that VPOP3 is not installed on a RAID 5 or RAID 6 array.

LAN Forward Warning: 452 (4.3.1 Insufficient system resources)

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

LAN Forward Warning: 452 (4.3.1 Insufficient system resources) If you get this message in VPOP3 it means that VPOP3 is trying to forward a message on to another mail server (probably Microsoft Exchange Server), and that other server is rejecting the message with the error

Move the message store - alternative method

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Move the message store - alternative method This method moves the database data storage location, but not the whole database. This means that the database configuration, logs, transaction logs etc are still stored in the VPOP3\pgsql\data folder, but the actual database tables & indexes are stored in the new location. This may be simpler, but, depending on your requirements,

MX Send Warning - .....

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

MX Send Warning - ..... If you see the text 'MX Send Warning - ' in the VPOP3 status monitor, that means that VPOP3 is trying to send a message to another mail server using the MX send method (direct to the recipient's mail server) and

VPOP3 - POP3 Client Connection Problem

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 - POP3 Client Connection Problem These errors occur during the period when VPOP3 is trying to establish a connection to your ISP's POP3 mail server to receive incoming mail. They can mean that you have entered the POP3 Server address incorrectly, or that there is a problem with the network, or that your ISP's mail server is not working properly.

Problems sending messages to spam@

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Problems sending messages to spam@ If a VPOP3 user forwards a message to spam@, 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.

Require SMTP Authentication

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

Restricting the number of recipients sent to

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Restricting the number of recipients sent to Some ISPs set restrictions on the number of recipients that you are allowed to send in a certain time period, eg 50 messages per hour, or the number of recipients that you are allowed to send per message or per connection.

Restricting the number of messages sent

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Restricting the number of messages sent Some ISPs set restrictions on the number of messages that you are allowed to send in a certain time period, eg 50 messages per hour, or the number of messages that you are allowed to send per connection. Restriction of messages per connection

Router Problem error messages

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Router Problem error messages If you get an error message to the VPOP3 administrator with subject Router Problem and text Local Distribute to Failed Error: Database Error "ERROR: could not open file "base//": Permission denied"

Sending mail from different email addresses or domains

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Sending mail from different email addresses or domains VPOP3 does not (by default) place any restrictions on which email addresses or domains you can send mail from. However, there may be external restrictions on which email addresses/domains you can send from. For instance, if you send mail through your ISP's mail server, they may only allow you to send mail from specific addresses, or the domain you send mail from may have a sender policy defined, such as

VPOP3 - SMTP Client Connection Problem

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

How to start VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

How to start VPOP3 There are two ways to start VPOP3 * as a service * as a normal application For normal operation, you will start VPOP3 as a service, as this means that VPOP3 will run even when no one is logged into the PC. To help with some types of problem diagnosis it can be better to start it as an application. This makes VPOP3 run in the account of the currently logged in user, rather than the service account, so it can eliminate access permission problems. Also, when VPOP3 starts a…

How to stop VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

How to stop VPOP3 You can stop VPOP3 by going to the Services applet in Windows, find the VPOP3 Email Server service and stop it, or, if you have the VPOP3 status monitor running with appropriate permissions, you can right-click that and choose 'Shutdown Server'

The message could not be loaded. Please return to the Quarantine page and try again

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

The message could not be loaded. Please return to the Quarantine page and try again This error normally means the message file has been deleted from the hard disk (probably by a virus scanner or something else on the PC). If you can find the message in the VPOP3 settings (Settings

Total Rebuild of Database

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Total Rebuild of Database If you suspect database corruption, sometimes the best thing to do is to totally rebuild the database. This involves six steps: * Stop VPOP3 * Backup Database * Delete Database * Re-create Database * Restore/Create Database

Transmission Receipt Message

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Transmission Receipt Message This is not an error message, but we are listing it here because it confuses some people. VPOP3 sends a 'Transmission Receipt' when a message is sent out, and it contains a header asking for the receipt. The default configuration is that it will send the transmission receipt if the sender asks for a read receipt.

How To Upgrade VPOP3 to version 5 or later

Anonymous (anonymous@undisclosed.example.com) — 2019-11-08T15:37:52+00:00

How To Upgrade VPOP3 to version 5 or later Upgrading VPOP3 is usually a straightforward process. Download VPOP3 from our web site and back up your current installation just in case something goes wrong. Then simply run the installer that you downloaded and install it over the top of your existing VPOP3. All your settings and mail will be preserved.

Upgrading VPOP3 to version 8.x from v7 or earlier

Anonymous (anonymous@undisclosed.example.com) — 2020-09-03T15:07:34+00:00

Upgrading VPOP3 to version 8.x from v7 or earlier VPOP3 v8.x uses PostgreSQL 10 as its database engine, which is the latest supported 32 bit version of PostgreSQL. Later versions of PostgreSQL are 64-bit only, which means we cannot use them while continuing to support 32 bit versions of Windows.

Upgrading VPOP3 to version 9.x from v7 or v8

Anonymous (anonymous@undisclosed.example.com) — 2026-03-18T20:49:54+00:00

Upgrading VPOP3 to version 9.x from v7 or v8 VPOP3 v9 and later requires a 64 bit version of Windows 8.1 or later VPOP3 v9.x uses PostgreSQL 18 as its database engine. This can only easily be upgraded from PostgreSQL 9.3 or later, which means it must be an upgrade of VPOP3 v7 or later. If you are using an earlier version of VPOP3, then upgrade it to v8.7 first, then upgrade to v9 or later

User receiving other users' messages

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

User receiving other users' messages Message Monitoring If the subject has a prefix starting with {mon- (eg {mon-internal, {mon-incoming, {mon-outgoing) then this probably means that you have set up Message Monitoring on your system, with the monitor target set to the person who is receiving the other users' messages.

Using a Mobile Phone with VPOP3

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Using a Mobile Phone with VPOP3 Many people want to use a mobile phone to send/receive their email nowadays. This is usually easy to do with VPOP3. The recommended way is to have the phone connect directly to VPOP3 for sending/receiving email. To do this, you need to do three things:

Using VPOP3 Advanced Features with LAN Forwarding

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

Using VPOP3 Spam Filtering with LAN Forwarding

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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.

Error message: VPOP3 Alert - Non-existent user -

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

Error message: VPOP3 Alert - Non-existent user - If you receive an error message like: Subject: VPOP3 Alert - Non-existent user - Delivery Failure Report. There was incoming mail for non-existent user "". This means that VPOP3 downloaded a message using POP3 and it was addressed to an email address which does not exist.

VPOP3 Antivirus Update Error - Error 11

Anonymous (anonymous@undisclosed.example.com) — 2025-10-06T15:24:19+00:00

VPOP3 Antivirus Update Error - Error 11 If you receive an “Error 11” when VPOP3 Antivirus is attempting to upgrade, then this means that it cannot download the antivirus updates from the Internet * Make sure you are using the latest version of the VPOP3AV plugin. You can check the version in the Settings

VPOP3 Antivirus Update Error - Error 55

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 Antivirus Update Error - Error 55 If you receive an “Error 55” when VPOP3 Antivirus is attempting to upgrade, then this means that the virus definition database is not readable. If you have VPOP3 Antivirus version 1.0.6 or earlier (check on Settings

VPOP3 Deleting messages as 'old' messages

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 Deleting messages as 'old' messages If VPOP3 says 'deleting old message' in the status window activity log that means that it has seen the unique ID of that message before, longer ago than the time specified for VPOP3 to leave messages on the server, so it thinks that the message is an old message, and so deletes it.

VPOP3 Historical Logger Backlog

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

VPOP3 Historical Logger Backlog This problem is primarily related to VPOP3 versions 2.5 -> 2.6. Theoretically it could happen on later versions, but would be extremely unusual (see the note at the bottom if you are using version 3.0 or later) You get an error message with subject

Error Message - VPOP3 xxxx Server Access Not Allowed - See Your Administrator

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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)

Error message: Your connection has been blocked temporarily - Try again later

Anonymous (anonymous@undisclosed.example.com) — 2018-11-14T10:45:49+00:00

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