Uninstalling a program can sometimes leave behind files and registry keys that can cause these errors. Spyware can also leave these files and keys as well.
Deleting the remaining files can sometimes correct the error. More often than not this doesn't correct the issue.
Most of the time deleting the remaining files corrects the error. Usually this doesn't fix the problem.
To open the default registry editor, click Start, then click Run... When the popup opens type in regedit and press the Ok.
Regedit opens it should have a menu at the top by default. Click Edit and select Find Next.
This will open a dialog box you can use to search for the keys left behind by the program. Once you locate the the keys, right-click on it and click Delete to remove the key.
Once you have them all deleted do one more search to verify they are all gone. Make sure you reboot after closing Regedit to check that this corrected the error.