Startup errors can be tricky to fix. Often spyware or malware can contribute to the error.
Sometimes you may uninstall an application and it fails to uninstall the app completely. Unfortunately, these registry keys were installed to properly start the original program and usually result in an error message on start up.
Deleting the remaining files can sometimes correct the error. More often than not this doesn't correct the issue.
Removing the files left behind usually fixes the error. Often though this doesn't fix the problem.
Often you'll have to use regedit to correct the errors. To open Regedit simply click Start, click Run, type in Regedit and hit Enter on your keyboard.
Once Regedit has opened click Edit at the top of the window. On the popup click 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.