I’ve been having the same problem for a couple months. I recently upgraded to Windows 8.1 (from Win7, did a proper hdd wipe) and the problem popped up again shortly after the installation.
Basically Avast won’t turn on. I see this screen:
http://i.imgur.com/bYlI3Uc.png
when I click ‘Resolve All’, the window freezes (goes into Not Responding mode) for about 60 seconds and then I get this other window:
http://i.imgur.com/fbHE12d.png
I click no but then it goes back to the first screen, Avast is still off. I still get periodic notifications of ‘Avast! Virus database has been updated’ but the thing still appears as off. I’m worried I might have a virus that’s doing this, maybe one of the programs I use is doing it and that’s why the problem persisted through a Windows reinstall.
I tried going into safe mode and doing a full scan. I also uninstalled Avast using the official uninstall utility in safe mode and then reinstalled it. It worked fine until the next restart, when it started misbehaving again.
Help. ;-;
- Latest, I think (2014.9.0.2018)
- Windows 8.1 Pro 64-bit
- Malwarebytes Anti-Malware and anything that came with Windows (like Windows Firewall and Windows Defender)
- None. I’ve been using Avast for many years
Any idea what my problem could be? 
Sounds very much like possible ‘remnants’ issue somewhere that’s corrupting your current installation.
Possibly not everything that needed to be ininstalled from previous installations was uninstalled.
Just a thought
system
6
I already tried that, like I said before. Even went on safe mode to run the uninstall utility. That was back in win7 though, I guess I’ll try again when I get back from work. Will post results then, thanks!