uninstall and clean tool from Microsoft Support

URL: http://support.microsoft.com/mats/Program_Install_and_Uninstall
(Fixit-portable)

What it fixes...

• Removes bad registry key on 64 bit operating systems.
• Windows registry keys that control the upgrade (patching) data that become corrupted.
• Resolves problems that prevent new programs from being installed.
• Resolves problems that prevent programs from being completely uninstalled and blocking new installations and updates.
• Use this troubleshooter for an uninstall only if the program fails to uninstall using the windows add/remove programs feature.