In order to fix the issue, you will need to reactivate Windows. Firstly, go to Start, type regedit and open the utility. Navigate to KEY-LOCAL-MACHINE > Software > Microsoft > Windows NT > CurrentVersion > WPAEvents, right-click the OOBETimer item from the right pane and select Modify. Select all value from the data box and then delete them. Click OK, close RegEdit and press Windows + R key combination. Type %systemroot%\system32\oobe\msoobe.exe /a in the Open field and click OK. In the Activate Windows wizard, check the box next to Yes, I want to telephone a customer service representative to activate Windows, click Next and press Change Product Key. Type the genuine key in the provided fields and then press Update.