I recently upgraded from Windows 7 Professional at home to Windows 10, and the install removed the license for Norton Ghost Version 15. In other words, my Norton Ghost Version 15 reverted to the status of demo/trial version. When I tried to enter the Norton Ghost Version 15 registration number, I got an error that the license number was incorrect and Ghost couldn't install the product. I checked, double-checked, triple-checked, but no dice. What am I missing?