I have a Windows 2003 SBS server setup with Exchange. The server checks the offsite e-mail server for e-mail every 15 minutes, and downloads it to the Exchange mailboxes. Everyone is using Outlook 2003, so they just download from the local server when they get into work, etc.
I have the server setup so it e-mails me (offsite) the server status every morning. For some time now, it comes up with errors relating to the downloading of e-mails, that all relate to the POP3 Connector. They only seem to affect two e-mail accounts - one more than others. Sometimes the longer the server is left without a restart, the more times the error occurs per day. Here are the error examples (I have replaced the real server and e-mail information with examples):
POP3 Connector, Event ID 1019, Total Occurences: 26
The message download process finished with one or more errors.
POP3 Connector, Event ID 1023, Total Occurences: 52
The downloading process for mailbox <email@example.com [pop3.example.com]> was ended with one or more errors.
POP3 Connector, Event ID 1035, Total Occurences: 52
A error occurred in connecting to the <pop3.example.com> POP3 server for user <firstname.lastname@example.org>. The error is 11004. The server may be down for maintenance or your server is not connected to the internet.
This user, and when it affects the other user, have not said anything about e-mails not coming through. Everything appears to be working at their end. But this problem didn't happen when the server was originally setup. At one stage I did remove the password on the account because we hadn't setup remote access and the user wanted to check webmail. By removing the password for that user in the POP3 Connector, I could then allow them to check webmail on our hosted system, without having to worry about the Exchange server downloading it and removing it from webmail.
Additionally, the second user for which the above error messages appear from time to time originally had their POP3 Connector setup with the wrong e-mail password (to check from our hosted service to download to the local server) initially - this has since been fixed and they are not having any issues.
I would like to know how to fix this issue, so that it doesn't happen again. One idea I had was to remove the user from the POP3 connector tool, then add them again - perhaps it would flush out any cache going on there? But I did not know whether this would delete any e-mails on the local server, or if the POP3 Connector is completely independent from that. So, I haven't done it yet.