https://wiki.pscs.co.uk/ 2026-05-06T12:43:45+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:err_mailbox_locked?rev=1542192349&do=diff -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… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:imap4?rev=1542192349&do=diff 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. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:ghost_folders?rev=1542192349&do=diff 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. 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:sharing_folders?rev=1542192349&do=diff Sharing IMAP4 folders Some email clients will allow you to share IMAP4 folders from within the client itself (eg eM Client) or have plugins to allow this (eg Mozilla Thunderbird with the Imap-ACL extension). In that case, you will need to see the documentation for that to set up sharing. 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: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: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: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:too_many_logins?rev=1542192349&do=diff "Too many logins" error message VPOP3 version 4 and later have a limit on the number of concurrent logins which can be received for a single user or from a single IP address. This is to prevent a single user from bringing the server down. The current default limits are 20 per user, or 1000 per IP address (to allow multiple people sharing a NAT IP address) 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 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:moving_messages?rev=1542192349&do=diff How to move messages between users There are several ways to do this, depending on your exact needs Via Administrator Console You can view a user's 'Inbox' messages by clicking on the message count on the Users list, then select the messages, choose the target user, and press the text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:outlook_behaviour_when_deleting_messages?rev=1542192349&do=diff Outlook behaviour when deleting messages from IMAP4 When you delete a message in Outlook it marks the message as deleted (putting a line through it). You have to 'purge' the mailbox to actually delete the message. See this Microsoft article for more information on this. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:performance_requirements?rev=1542192349&do=diff Performance Requirements The performance requirements for VPOP3 depends on many factors, so we can't give specific details for any scenario. How to detect limiting factors * Use the Windows Performance Monitor (perfmon.msc) * Add counters for: text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:pop3_webmail_imap4_can_t_see_messages_but_admin_can?rev=1542192349&do=diff POP3/Webmail/IMAP4 can't see a user's messages, but the administrator can Version 2.x only. This problem does not occur with version 3 or later. This problem can happen if the user's message index database has become damaged. The POP3, Webmail & IMAP4 services get the message summary data from the database, whereas the administrator console gets the message information directly from the message files on the disk, so if the database is corrupted, the administrator console can still see the mess… text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:restore_folder_v3?rev=1542192349&do=diff Restore a single user's mailbox or folder in v3 or v4 To restore a single user's Mailbox or folder is currently only possible in VPOP3 Enterprise, and requires a second PC to act as a temporary VPOP3 server. You need to: * Restore your latest VPOP3 backup to another PC (a temporary VPOP3 server) text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:using_a_mobile_phone_with_vpop3?rev=1542192349&do=diff 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: text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:android_-_stock_client?rev=1542192349&do=diff Android - Stock Client Warning If you use the stock email client from Android 4.x, then be VERY careful if you are using POP3 download. It appears that the stock client will download all the messages from your mail server every time it checks for mail, so you could use a 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: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:full_text_search?rev=1542192349&do=diff 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. 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:inbox_size_is_zero_but_mailbox_size_is_not_zero?rev=1542192349&do=diff Inbox size is zero but mailbox size is not zero In the VPOP3 settings sometimes, on the user account list the “Inbox Count” is shown as zero, but the “Mailbox Size” is not zero. This is not a bug, or mistake - the two figures are showing different things. text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:not_working_as_expected?rev=1542192349&do=diff Not Working As Expected This is the page to come to if you think you've set something up correctly but it isn't doing what you think it should be doing. If you're getting an error message or some other concrete indication that something has actually 'gone wrong' then the text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:sending_mail_from_different_email_addresses_or_domains?rev=1542192349&do=diff 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 text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:undelete?rev=1542192349&do=diff Undelete Messages in VPOP3 Enterprise v5 or later If a user accidentally deletes messages or a message folder, you can easily undelete this within a few days. The amount of time that messages are stored in the VPOP3 'recycle bin' is set in Settings text/html 2018-11-14T10:45:49+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.pscs.co.uk/how_to:vpop3_2.x_crashes_when_user_tries_to_download_mail?rev=1542192349&do=diff VPOP3 2.x crashes when user tries to download mail If VPOP3 2.x crashes when a user tries to download mail, there are a few possible causes we know of: * A virus scanner or Internet security software is interfering with the connection between VPOP3 and the email client and is either terminating VPOP3 deliberately, or is blocking VPOP3 causing another part of it to crash 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: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)