alanrf, you're probably right that after all, WebShield CAN handle MSN's HTTP interface for fetching emails. However, what's certainly confusing is the way it reports a virus, if found. That is, the standard WebShield virus dialog, with the "Abort Connection" button, somehow doesn't work in this scenario. Clicking that button simply aborts downloading of the email (or all emails) - and that's probably not what we'd hope for in this case. The same of course happens on each and every successive attempt to grab email (until WebShield is stopped, or the offending message is deleted from the server - possibly from another machine).
That's why we're somehow reluctant to including mail clients to the default optin list.
Cheers
Vlk