OK, but the mailshield attachment checkbox is checked. Aren't the attachments typically the virus package? Plus the real-time scanner should pick up on the email, it's getting downloaded onto my computer hard drive.
I'd rather have an answer to how to increase the limits.
It won't work.
There is no mail shield attachment check box. There is a scan Attachment option in your image, but you haven't checked it and importantly this is (
MS Outlook only).
There is the Enable Mail Shield option, Enabled (an Avast component), but you effectively disable that by NOT having it scan Inbound and Outbound email scans as has been said previously, hence no connection errors.
And you still haven't posted a screenshot of those errors!
So yes, you are going to have to wait from some input from an Avast Team member.