Hi, I came across the same problem after purchasing the $23 upgrade for scanning and its been “scan failed” every time in the Virus row after scan completes.
I tried getting the GUID in the way you explained but i keep failing to get anything to pop up or anything to copy.
What can I do to get an answer?
EDIT*
Not sure this is relevant but i thought I’d give it a shot anyway.
Program version: 12.3.2280 (Build 12.3.3154.6)
Virus definitions version: 160928-1
Number of definitions: 4,884,002
A good start would be explaining what the problem is.
Secondly, you need to provide details.
What exact avast version ?
What OS/SP ?
Any other security (related) software installed ? (or was there)
Already performed a repair of avast ?
Already performed a clean installation of avast ?
What are the last entries in the log file ?