Your using Outlook 2003?
Cool, then just disable the avast Internet mail service and that’s it. Outlook is handled separately, by the Outlook/Exchange plugin.
Go to Start → avast Antivirus → Mail Protection Wizard, and choose Remove protection from all my accounts.
BTW do you see the avast splash screen when starting Outlook? If not, make sure avast is not listed in the Disabled Items field, accessible from within Outlook About box…
But you can use Internet Mail provider for MS Outlook too right? Or you can use only Outlook/Exchange provider?
If it’s used to pop mail using POP3/IMAP4 (in opposite to Exchange Server), then yes. But I recommend against it - the Outlook provider is much more flexible. And the Mail Protection Wizard does not support Outlook, so you’d have to set it up manually.