NOTE: The original Microsoft Fix It tool was offline for a day and now as of Feb 4th, 2015, it's back. This newer Fix It Solution Center has always worked.
1. Visit Microsoft Support at http://support.microsoft.com/fixit/
2. Select "Install or upgrade software or hardware" listed in Section 2
3. Click the "Run Now" button in Section 3 next to "Fix problems that programs cannot be installed or uninstalled."
4. Click the "Run" button in the install dialog box. Microsoft will download and install the Fix It Engine on your computer.
5. Select "Detect problems and apply fixes for me" from the Fix It dialog box.
6. Select the program you wish to uninstall from the list and click the "Next" button.