OK I think I have the picture of the underlying issues as to what the other issue was. Unfortunately as you found you end up chasing problems caused by the actions taken to try and resolve the original problem up to the point the original problem is a distant memory.
So can you try to answer the other questions relating to aswClear.exe:
When you ran aswclear.exe why didn't it work, e.g. what errors reported, etc. ?
Did you run this from, safe mode ?
If not that could be why it didn't work, see booting into safe mode http://www.pchell.com/support/safemode.shtml
If the uninstall was partially successful it may have removed the program files folder and that would be needed as a reference point for the uninstall utility, so you may need to create these folders. Assuming that you installed avast into the default location create the avast folders (red) C:\Program Files\Alwil Software\Avast4
in the Program Files folder.
Boot into safe mode and run the aswClear.exe file.