Did you install avast! and boot?
The Mail Protection Wizard is automatically called for protect your emails accounts...
If not, click in the icon on the Start Menu > avast! antivirus.
Run the MPW and choose 'not Outlook' but 'Outlook Express' and 'Protect all my accounts created in the future'...
Oh, don't forget, all of this must be done with Outlook Express closed or nothing will be done correctly...
Good luck. Wellcome to forums.