First off, you're polling far too frequently. One minute does not allow
enough time to connect to the server, poll for mail, start the download, and
have your antivirus scan everything coming in and then going out before
Outlook is polling again.
Set your polling frequency for no less than 5 minutes but 10 is better.
Also, you can safely stop scanning your incoming and outgoing mail with your
antivirus programme. Your real time scanner will catch whatever it's updated
for.
If there is a receiving server related error, what does it say exactly? It's
very hard to determine what's happening if there is an error but you don't
know what it is.