Upon running the Activation troubleshooter, Windows displays the following message- Unable to activate Windows. We can’t reactivate Windows as our servers aren’t available right now.

If after a hardware change and you encounter Error Code 0x803FABB8, Donor hardware ID does not own operating system entitlement, see this fix.

Solution 1: Run Windows Activation Troubleshooter The steps in this solution is applicable to computers running on Windows 10.