After installing avast I see the option “hide protected operating system files” in the folder options disappeared. This is the first time this happened for me. I spent an hour searching for a solution till I found a registry fix to show this option again. Please tell me if avast is hiding this option or it is something else. I’m using windows xp sp3 fully updated.
This isn’t changed by avast.
The image you show is a windows explorer folder options default setting. So why the actual item (not just being checked or not) should still be present.
That has never changed in either of my systems and on XP on many different versions of avast for over seven years.
+1
Either other application that you install is causing this, a malware, or somebody else using your computer messing with your registry.