Once, a very long time ago, I started getting these windows about wanting to change my file associations. At first I thought it was legitimate and clicked "yes" to the first couple. But they just kept popping up and I decided something was wrong. I ran into trouble on the two or three I had clicked "yes" on to start with. I think that is when I found and installed that Unassoc.exe program. But I haven't used it since. So now I started getting these windows popping all over the place again today for the first time since that long-ago occurrence. I had actually forgotten that I even had that Unassoc.exe.
I am very puzzled about this Win32:Malware-gen thing. When Avast first found this during a full scan on Sunday I placed it in the chest and that particular file is still there. Then Avast suggested a boot scan so I went ahead with that. It showed another Win32 infection in the same location, but a different installer, C\Windows\Installer\a6d64.msi. It would not allow me to put in the chest or to repair with an error 42111. I ended up doing the boot scan again later and it showed that infection. I looked in that location on my hard drive yesterday and found the file. I right-clicked on it several times throughout the day to scan with Avast and each time Avast showed the threat that was indicated during boot scan. I just went back and scanned that file again and now it shows no threat.
I got another program update come through on Avast this morning, which surprised me because I just had a major program update. Is there any possibility that this was some kind of false positive glitch by Avast, which has now been fixed by this update? If I have wasted your time I am very sorry for this because I see there are a lot of people needing help. I almost wonder what another boot scan would show. I may go ahead and do another boot scan and will let you know if this comes up again.
On your question as to how the computer is behaving, until the things I reported happening just this morning, it was behaving fine. It seems to be fine again now, but can't help wondering what was causing all that flurring this morning.