Another thing that I've noticed is that while the rule in Mail preferences is Active and Avast Mail Support is not ticked, all new email received is highlighted in an alarming pink colour.
I hope this helps.
Tim
I just "upgraded" from 2.74 to 3.07 last night. I do not have mail support enabled, however since installing 3.07 90% on my incoming mail is highlighted "orange".
Guess I should check mail for that "rule" as well.
Please, make sure that the rule is there. clicking mail preferences on/off in avast's preference pane should do the job. otherwise, go to mail's preferences a nd verify whether avast's rule is there.
to be honest, the mail's support for this third-party scanning via applescript is notoriously buggy and inconsistent, and the whole feature turned into one big workaround

.
especially, this adding of new rule sometimes needs mail's restart, otherwise the rule is active, but forgotten when the mail quits upon logout. strange enough, but this is how it's implemented.
we'll try to make it more bullet-proof, or at least we'll inform users about this Mail's flaw.
regards,
pc