Every application icon in folder REPLACED with Avast icon

My friend just try for using Avast. But at the 1st run, every installed games detected as virus.
So he try to make exception on his entire games folder but the problem is… every application icon’s on that folder had replaced with Avast icon. Tried to reinstall but the icon stay the same. The games still playable though.

How to revert back to their original icon?

every installed games detected as virus.
what malware name does avast give?

Post a screenshot se we can see