Interestingly enough, if you do a repair installation (an Upgrade install over an existing installation) of Windows, Zune’s driver apparently disappears.
I recently did a repair install myself and to my dismay, my Zune no longer synced when I attached it via the cable to the USB port of my laptop. Windows said that it needed a driver all of a sudden and when it searched Microsoft Update for the driver, it came back empty. I pointed to the original install files and no joy: Windows didn’t find the driver there either.
The obvious solution is to simply uninstall the Zune software and reinstall it, to make sure that the drivers got installed into the OS. Of course I was a little worried: I didn’t want to have to reinput all of my podcast URLs – especially since I had no idea where it stored this information on the drive.
Fortunately, all that configuration information remained after I uninstalled the software and reinstalled it. And as expected, once I did that, Windows picked up my connected Zune immediately and started the process of syncing the new podcasts and clips I’d made available.
So the good news is that the workaround is simple.
The bad news is, why is getting the Zune driver such a pain in the butt?
Kurt's Thoughts 
when you re-installed the program did it keep all the music etc, you previously had? including ones you removed from the collection?
ok forget my last comment, uninstalling it didnt work for me thanks though