Avast Home:
Some other applcation removed some dlls on uninstalling (msvcr71 msvcp71 mfc71).
THEN:
Avast doeas not start, does not uninstall
GREAT WORK!
Easy way to down anvir protection at all !!!
I suppose it is bad way to use such shared libs for such security critical application!
Regards
Which is your Windows? 98, Me, XP, Vista?
Do you use any other antivirus in your computer?
Can you try to repair your installation?
Go to Control Panel > Add/Remove programs > avast! antivirus > Remove. Then choose Repair function in the popup window (Repair).
If this does not help, can you uninstall / boot / install / boot again?
Or you can remove kernel32.dll, user32.dll and gdi32.dll…
I mean, it’s of course not the same thing, but the bottom line is that once the attackers gets write access to the system folder it can do any harm to the system.
Of course, not the same. 
BUT shared files are not protected for uninstallers. :o
I think engineeres SHOULD analize that case.
I suppose that dll’s will be more protected at the avast program files folder
2 Tech:
Vista x64
Comodo firewall
Uninstaller did not work.
I’ve copied 3 dll’s from the work computer and turned avast service on - all works again.
In these cases you can download the latest version of Avast Uninstall and use it for complete uninstallation. If, for any reason, you can’t run it, try booting in Safe Mode and doing it from there.
I think the non-admin users need that the dll be on the shared folder… maybe I’m wrong.
Yes, I’ve copied to system32 folder
I was talking about that folder… (in opposition to avast folder).