H Mac,
Yes, Outlook as part of Microsoft Office 2011 on a MacBook Pro. I get no warnings as to the failure, the emails just do not show up. Fortunately, I have one of those email addresses on my IPad, so noticed I wasn't getting them on my Mac. I have a reseller server account with Hostgator, and it was pretty much all of those website accounts on my server whose emails ALL failed. Could it be something to do with that server and IP that got onto some sort of black list that Avast listed in their algorithms and that is why I can't receive emails? I know websites, emails not so much. :-(
Thanks so much for your help and interest in this!
Janell