Office 2010 invalid product key after rolling back to Windows 7

mjcarp Posts 1 Registration date Sunday October 11, 2015 Status Member Last seen October 11, 2015 - Oct 11, 2015 at 08:07 AM
I upgraded to windows 10 but did not like it and when I rolled back to windows 7 it crashed my hard drive. I had to reinstall the OS and my Apps. I had a valid license key for Office 2010 but when I try to reinstall Office 2010 I am getting an invalid product key and cannot activate office 2010. ?

any ideas how to recover my valid license as it wiped out the product key