Hum...
Here is a registry entry I use to install all my program to the D:\ drive (that way, I can wipe out windows and keep my program's configuration):
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion]
"ProgramFilesDir"="D:"
When I open a setup file, it ask me to install the application in "D:\<application name>"
Maybe I could try to change "D:" to "D:\" but that would need some testing...
But why should I have problem if the path misses a "\"? I could understand my problem if I've put "D:\" and avast just add "\Avast" to the path, so it ends up with "D:\\Avast"... But the reg key is "D:" so even if avast add "\Avast" to this, its just one "\"!
Or maybe windows adds a "\" itself to the reg key? I'm not a developper so I don't know the avast's and windows' behavior...
Btw, I think it's not a good idea do have their D:, without the backslash. If avast! appends another backslash in this case, then it's a bug and will be fixed.
I'll try setting the key to "D:\" and post the results later....
thanks!