Uninstalling Toad is not so easy at at seems.
From my experience here are next folders you must completely delete after
classic uninstalling Toad:
c:\Program Files\Common Files\Quest Shared
c:\Program Files\Common Files\Quest Software
Thise are diretory structure on MS Vista/MS Server 2008. For x64 version replace
c:\Program Files\ with c:\Program Files (86)\
To be sure grep all directories on your system disk and profiles (where you
private files are saved) for “Quest” pattern.
If your Toad is unstable then this i smore then recommended before upgrading to
new version. You will loose all settings but new version will be really stable
Hope this helps,