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       <dc:date>2026-05-06T13:08:39+00:00</dc:date>
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    <item rdf:about="https://wiki.pscs.co.uk/how_to:database_maintenance?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Database Maintenance</title>
        <link>https://wiki.pscs.co.uk/how_to:database_maintenance?rev=1542192349&amp;do=diff</link>
        <description>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…</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:backup_vpop3?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>How to Backup VPOP3</title>
        <link>https://wiki.pscs.co.uk/how_to:backup_vpop3?rev=1542192349&amp;do=diff</link>
        <description>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&#039;s backup, DBBACK-1.DMP is Monday&#039;s backup, etc).</description>
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    <item rdf:about="https://wiki.pscs.co.uk/how_to:delete_an_outgoing_message?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Delete an outgoing message</title>
        <link>https://wiki.pscs.co.uk/how_to:delete_an_outgoing_message?rev=1542192349&amp;do=diff</link>
        <description>Delete an outgoing message

To delete an outgoing message, go into the VPOP3 settings, then go to the &#039;Users&#039; page. At the top of the page will be a line saying Outgoing Message Queue. Click on that line, and this will show you all the messages waiting to go out. You can now select the message(s) in question, and press the</description>
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    <item rdf:about="https://wiki.pscs.co.uk/how_to:error_creating_service_entry_vpop_-_5?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Error creating Service Entry (VPOP3) - 5</title>
        <link>https://wiki.pscs.co.uk/how_to:error_creating_service_entry_vpop_-_5?rev=1542192349&amp;do=diff</link>
        <description>Error creating Service Entry (VPOP3) - 5

If you get this error while running VPOP3SVC QuickConfig to install the VPOP3 service this might mean that some security software is blocking it from creating the service.

This has been observed with Sophos Antivirus. In that case, go to the Quarantine Manager in Sophos, and</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:error_expanding_recipient_-_nesting_level_too_deep?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Error expanding recipient - Nesting Level too deep</title>
        <link>https://wiki.pscs.co.uk/how_to:error_expanding_recipient_-_nesting_level_too_deep?rev=1542192349&amp;do=diff</link>
        <description>Error expanding recipient - Nesting Level too deep

You receive an error message saying:
Error expanding recipient &quot;&lt;email address&gt;&quot;
Nesting Level too deep (51)
Check the configuration for loops

(Note the &#039;51&#039; number may be slightly different - that&#039;s the nesting level - anything over 50 is detected as an error)</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:error_messages?rev=1759764097&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2025-10-06T15:21:37+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Error Messages</title>
        <link>https://wiki.pscs.co.uk/how_to:error_messages?rev=1759764097&amp;do=diff</link>
        <description>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</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:error_sending_message_after_authentication?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>&quot;Error Sending Message After Authentication&quot; in Webmail</title>
        <link>https://wiki.pscs.co.uk/how_to:error_sending_message_after_authentication?rev=1542192349&amp;do=diff</link>
        <description>&quot;Error Sending Message After Authentication&quot; 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…</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:exceptions?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Exceptions</title>
        <link>https://wiki.pscs.co.uk/how_to:exceptions?rev=1542192349&amp;do=diff</link>
        <description>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&#039;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.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:move_the_message_store_-_alternative_method?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Move the message store - alternative method</title>
        <link>https://wiki.pscs.co.uk/how_to:move_the_message_store_-_alternative_method?rev=1542192349&amp;do=diff</link>
        <description>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 &amp; indexes are stored in the new location. This may be simpler, but, depending on your requirements,</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:non-administrator?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Trying to perform administrative tasks without rights</title>
        <link>https://wiki.pscs.co.uk/how_to:non-administrator?rev=1542192349&amp;do=diff</link>
        <description>Trying to perform administrative tasks without rights

This problem can have two symptoms:

	*  When trying to access the VPOP3 settings you get an error “You are trying to perform an VPOP3 administration task while logged in as a non-administrator</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:not_working_as_expected?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Not Working As Expected</title>
        <link>https://wiki.pscs.co.uk/how_to:not_working_as_expected?rev=1542192349&amp;do=diff</link>
        <description>Not Working As Expected

This is the page to come to if you think you&#039;ve set something up correctly but it isn&#039;t doing what you think it should be doing. If you&#039;re getting an error message or some other concrete indication that something has actually &#039;gone wrong&#039; then the</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:outlook_outlook_express_are_sending_mail_repeatedly?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Outlook / Outlook Express is sending mail repeatedly</title>
        <link>https://wiki.pscs.co.uk/how_to:outlook_outlook_express_are_sending_mail_repeatedly?rev=1542192349&amp;do=diff</link>
        <description>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</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:performance_requirements?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Performance Requirements</title>
        <link>https://wiki.pscs.co.uk/how_to:performance_requirements?rev=1542192349&amp;do=diff</link>
        <description>Performance Requirements

The performance requirements for VPOP3 depends on many factors, so we can&#039;t give specific details for any scenario.

How to detect limiting factors

	*  Use the Windows Performance Monitor (perfmon.msc)
	*  Add counters for:</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:recovering_messages_from_corrupted_database_into_fresh_database?rev=1757598487&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2025-09-11T13:48:07+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Recovering messages from corrupted database into fresh database</title>
        <link>https://wiki.pscs.co.uk/how_to:recovering_messages_from_corrupted_database_into_fresh_database?rev=1757598487&amp;do=diff</link>
        <description>Recovering messages from corrupted database into fresh database

If the VPOP3 message database is corrupted, then one option is to build a fresh database and restore the settings into it, then recover the messages from the old database using the &#039;Message Restore&#039; function in VPOP3. This has minimal downtime, but old messages will not all be available until the restore has completed. New messages will be available quickly, and you will be able to send messages.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:repairing_corrupted_database?rev=1705318545&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2024-01-15T11:35:45+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Repairing corrupted database</title>
        <link>https://wiki.pscs.co.uk/how_to:repairing_corrupted_database?rev=1705318545&amp;do=diff</link>
        <description>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&#039;t then there is no manual &#039;repair&#039; function, because the data cannot totally be recovered (or it would automatically have been recovered).</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:restore_folder_-_v5?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Restore selected mail folders or mailbox in VPOP3 v5 or later</title>
        <link>https://wiki.pscs.co.uk/how_to:restore_folder_-_v5?rev=1542192349&amp;do=diff</link>
        <description>Restore selected mail folders or mailbox in VPOP3 v5 or later

(This option is only available in VPOP3 Enterprise)

First - if the problem is that messages were deleted very recently (the default is within 3 days), you can probably use the Undelete feature in VPOP3.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:sender_domain_must_resolve?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Sender Domain Must Resolve</title>
        <link>https://wiki.pscs.co.uk/how_to:sender_domain_must_resolve?rev=1542192349&amp;do=diff</link>
        <description>Sender Domain Must Resolve

If you receive an &#039;SMTP Client Error&#039; something like:

451 (user@domain.com) Sender Domain Must Resolve

this means that the ISP&#039;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</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:timeout_while_vpop3db_is_starting?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Timeout while VPOP3DB is starting</title>
        <link>https://wiki.pscs.co.uk/how_to:timeout_while_vpop3db_is_starting?rev=1542192349&amp;do=diff</link>
        <description>Timeout while VPOP3DB is starting

(Note that VPOP3 v6.11 and later, the service startup system has changed so it should not suffer from this problem)

When VPOP3DB starts up, the service control manager component waits a set time for a response from the database server before it knows the service has started. If the PC is going slow (eg after a Windows update or if the PC is just slow) then this wait may not be long enough.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:total_rebuild_of_database?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Total Rebuild of Database</title>
        <link>https://wiki.pscs.co.uk/how_to:total_rebuild_of_database?rev=1542192349&amp;do=diff</link>
        <description>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</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:troubleshooting_tips?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Troubleshooting Tips</title>
        <link>https://wiki.pscs.co.uk/how_to:troubleshooting_tips?rev=1542192349&amp;do=diff</link>
        <description>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.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:upgrade_vpop3_to_version_8?rev=1599145654&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2020-09-03T15:07:34+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Upgrading VPOP3 to version 8.x from v7 or earlier</title>
        <link>https://wiki.pscs.co.uk/how_to:upgrade_vpop3_to_version_8?rev=1599145654&amp;do=diff</link>
        <description>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.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:vpop3_not_starting_properly?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>VPOP3 Not Starting Properly</title>
        <link>https://wiki.pscs.co.uk/how_to:vpop3_not_starting_properly?rev=1542192349&amp;do=diff</link>
        <description>VPOP3 Not Starting Properly

If VPOP3 is not starting properly, then the first thing to check is whether the database server is starting. In VPOP3 v3 and later, VPOP3 uses a PostgreSQL Database server for data storage, so if the database server is not running, VPOP3 will not be able to start properly. In this case, the VPOP3.EXE process may appear in Task Manager, but it won&#039;t respond to anything, or it may appear in Task Manager and then stop after a short period.</description>
    </item>
    <item rdf:about="https://wiki.pscs.co.uk/how_to:whitelist_blacklist?rev=1542192349&amp;do=diff">
        <dc:format>text/html</dc:format>
        <dc:date>2018-11-14T10:45:49+00:00</dc:date>
        <dc:creator>Anonymous (anonymous@undisclosed.example.com)</dc:creator>
        <title>Spamfilter Whitelist &amp; Blacklist</title>
        <link>https://wiki.pscs.co.uk/how_to:whitelist_blacklist?rev=1542192349&amp;do=diff</link>
        <description>Spamfilter Whitelist &amp; 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 -&gt; Spamfilter -&gt;</description>
    </item>
</rdf:RDF>
