If you have a Microsoft keyboard or mouse not responding as expected in the Finder, such as inability to rename hard drives, folders, or type anything in the Finder, but works in other applications, or certain functions aren't enabled by Apple menu -> System Preferences -> Keyboard & Mouse, it can be a sign that the Intellipoint drivers need to be installed, or updated:
Lists the most current version of those drivers. Make sure the version you use has been tested with the operating system you are running.
I found this problem existed with the Microsoft Natural Form keyboard connected to a PI USB AT connector. It wouldn't rename the hard drive even when the text was highlighted and the hard drive name was outlined. Installing the Intellipoint drivers on a Mac Pro solved the problem.