DavidR
4
Thanks DavidR for yr quick response. It is now set as 'Show detailed info on...'
This is not the same, you will be inundated with detailed info at the bottom of the screen, which is for every email received and not warning pop-up alert.
The arrows are pointing at Silent mode and its options, ensure those aren’t ticked. If they aren’t ticked then it is something else. Try a repair of avast. Add Remove programs, select ‘avast! Anti-Virus,’ click the Change/Remove button and scroll down to Repair, click next and follow. You need to be on-line to do this. Let us know if this resolves the problem.
I suggest you try a test by sending from an outside source by emailing the eicar test from this site http://www.gfi.com/emailsecuritytest/, it might be no different but worth a try, uncheck the other email tests and leave only the Eicar test ticked (see image).
As you mention you may have other OS problems and more difficult to locate.