I recently installed Google toolbar to get "BlogThis" functionality. Alas, I soon discovered that as I use the new beta blogger, this functionality is not supported in the current version of the toolbar :( However, more annoyingly, the toolbar seems to break the right-click context menu..
So I wanted to get rid of the toolbar as soon as possible (at least for the time being).
Now comes the big problem, the thing won't let me uninstall it, complaining about unsufficient permissions, yada yada. Basically because of UAC even though you have admin privileges you are not running with them all of the time. A properly configured installer will ask for elevated privileges, but it seems the Toolbar installer is not clever enough to do this..
So here's how you do it:
Right-click IE icon, choose "Run as Administrator", and then proceed to uninstalling the toolbar. Needless to say, it is probably safest to not go around surfing the 'net as Administrator...