Outlook Express pop3 problem

[rsmyth]

I have Windows XP Home edition SP2. I am using OE 6. I am using AVG free edition. Zone Alarm Free edition. I also have been testing lately Thunderbird (I always made sure to use only one email client at a time). Everything worked fine but one day everything, my website, webmail and email client stopped working. The next day everything was working except my POP3 incoming mail on my Outlook Express or any email client. Webmail works fine. The exact error message is:

The server responded with an error. Account: 'mail.mydomain.com', Server: 'mail.mydomain.com', Protocol: POP3, Server Response: '-ERR AVG POP3 Proxy Server: Cannot connect to the mail server!', Port: 110, Secure(SSL): No, Server Error: 0x800CCC90, Error Number: 0x800CCC90

I posted this problem in the AVG forums and I was told it is an email problem. Not AVG. I dont understand that because AVG is being mentioned in the error.