Many of the regulars here would say that using anti-virus to scan incoming causes more trouble than it saves; many AV products can seriously damage your mail store, especially when they try to quarantine a whole folder just to deal with one suspicious message. I'd suggest you disable scanning of incoming mail, and use the real-time scanning component to catch anything when it tries to run. Your mail client and server are very sensibly using encryption to protect your login and password from being seen en-route. AVG is complaining because it can't read the encrypted data. I'd rather have the security of the encryption than the dubious advantage of some scanning that ''may'' catch bad stuff. I don't use AVG (nor Windows) myself, so I can't say for sure, but I was under the impression that current versions of anti-virus can themselves use encryption, and thereby work with the encrypted connection. If AVG won't, maybe it's time to look for an AV package that can. But I would urge you to drop the live scanning of incoming email.