- Run System Restore to create a new Checkpoint. So that you can rollback if something goes wrong
- Start regedit and change at least one digit of the "oobetimer" value :
[HKEY_LOCAL_MACHINE \SOFTWARE \Microsoft \Windows NT\CurrentVersion \WPAEvents]
oobetimer = ? (Change at least one digit)
- Start the Windows Product Activation (WPA) screen by running this command :
- At the activation screen, select the option to "Activate by Phone"
- At the product key change screen, type in your new product key (Make sure to use a key which match your Windows license)
- If it returns to the activation screen, after typing in the new key, click "Remind me later"
- Close the window and reboot the machine
- After the reboot run the command to start the Activation Screen again and make sure that it says "Windows is already activated"
More Info MS KB328874
More Info MS KB842196
More Info MS KB918342
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