Hi, does the program still appear in your Start>All Programs list, if so does it have a uninstall option when you hover your cursor over it - if yes, uninstall it from there - if no, look in Control Panel>Add/Remove list, if it shows there, uninstall it.
If neither of the above - go to Start>Search, opt to look in All files and folders, click on Advanced and include Hidden files and folders in the search. Type in name of the program and hit Return. If Search finds anything appertaining to the program, highlight the entries in Search and then press Del on keyboard.
If none of the above works, download and run click here
Let RegScrub find all problems, then click on Fix all problems ... don't be surprised if it finds hundreds of problems, this is not unusual, let it fix the lot, will only take a few minutes. When that has finished do a normal Restart of your computer - hopefully no more annoying message.