Cleaning every last trace of an old program can be a pain. 

Here's how to do it quickly, in about 5 minutes:

1. Open the ‘Programs and Features' control panel, select the application you no longer want, and click Uninstall. You may need to reboot the system. 

2. If the program has other parts (plug-ins, toolbars, ActiveX components, and so on), uninstall them too, following the above instructions. If an application won't uninstall, don't edit the Registry in an attempt to manually scrub the program away; in all likelihood, you'll accidentally cause more harm than good.

3. If you installed the program recently, you can try rolling back your PC with System Restore to get rid of it. Find this function under Accessories, System Tools.

4. If that doesn't work, try the  Revo Uninstaller.