Regedit has a problem opening the specified key.
Fix any registry problems. Use a registry fixer tool to accomplish this. A good registry fixer will fix or remove bad entries and orphaned entries left over from a badly behaving uninstall.
One registry fixer tool that stands out in competitive reviews is part of Fix-It Utilities Professional and SystemSuite Professional.
Check out what others say about this issue and review or add your own comments and solutions!