I don't have other HTTP account but the rest of the POP3 accounts are working fine.
Everything is going well accept Hotmail.
Are you sure that it is avast! the problem here?
I've heard that Hotmail changed a little when it allowed only 'paid' versions.
Can you send mail by Hotmail? Or you can't receive and send... :'(
When you're checking Hotmail, does any special process is started? I mean, if you click CTRL-ALT-DEL, can you see any different 'program' running there? If so, you've be able to add the line
IgnoreProcess=<name> into avast4.ini file to exclude it...
Hotmail/Yahoo is not a pop3 email service (unless you pay for pop service), it is web based (so the Internet Mail provider doesn't directly protect it). Web based email is simply your email being viewed in the same way you browser the internet. The pages (that display your email) are downloaded into your Temporary Internet folder, just like regular web pages and displayed on your browser screen.
The Standard Shield will scan your files (as they are downloaded into your Temporary Internet folder) when sensitivity is set to High. You can round this 'problem' using 3rd party applications to download the Hotmail messages through the pop3 server (PopHotmail, for instance).