Reactivating Windows 10 upgrade

After a Mainboard and CPU change (caused by defect) Windows 10 prompted, that there is no valid activation. When trying to activate, Windows returns, that the key has been deactivated.

This way to recover the system without data-loss worked fine for me:

  • Create an empty partition (I resized one disk with MiniTool Partition Wizard free
  • Install Windows 7 with SP1 on this epty partition (took around 20 mins)
  • Activate Windows 7
  • Update Windows 7 to Windows 10 (took another 20 mins)
  • Check for valid activation
  • Boot to original Windows 10 (eventually use EasyBCD to correct BCD
  • On second reboot of Windows 10 activation showed active again (I am not sure if it needs 2 reboots or just takes more time)