system
20
as long as a couple of setup files are affected, it’s not a problem, but if some system files (like user32.dll) or program files start to be detected as well, then it’s more serious and would require a complete deactivation of Avast AV, at least until the database is good again. It hasn’t happened on my system so far (concerning windows files), but if it did I’d switch immediately to another antivirus.