Knowledgebase
How to fix the error 0x800CCC0F when receiving mail with Outlook Express and Windows Live Mail
Before you try any other solution make sure you're not disconnected from the Internet, and also check the settings for the troublesome email account.
One reason for getting this error code in Outlook Express and Windows Live Mail when receiving mail, with both POP and IMAP incoming server type, is an incorrect port number. If you have enabled encryption for the incoming mail server but you have changed the port number to the non-encryption one (110 for POP, 143 for IMAP), you'll get the error number 0x800CCC0F. So make sure that if you have enabled encryption the port numbers are correct: 995 for POP, 993 for IMAP. In case the port number is incorrect the error message in Outlook Express will look like this:
our server has unexpectedly terminated the connection. Possible causes for this include server problems, network problems, or a long period of inactivity. Account: 'servername.com', Server: 'servername.com', Protocol: POP3, Port: 110, Secure(SSL): Yes, Error Number: 0x800CCC0F
As you can notice in the error message, SSL is enabled but the wrong port number is used. The error message in Windows Live Mail is almost the same.
Another “all time favorite†reason for getting this error number is your antivirus software or firewall. Disable your antivirus application, or even uninstall it, to make sure it's not causing this problem.
If you need more information on configuring Outlook Express or Windows Live Mail to use your email account read the respective tutorial.