You didn't specify which version of Corel you are try to install,
Is there a folder named: C:\program files\corel\Corel VideoStudio Pro X (the X is followed by a version number which should be older then the version you are trying to install) on your computer?
If so then Google: https://www.google.com/search?q=totally+remove+corel+videostudio&ie=utf-8&oe=utf-8
You may also want to try contacting Corel Tech Support: http://www.corel.com/us/support/
J W Stuart: http://www.pagestart.com