- Click on start menu.
- Type cmd in search field.
- Right click on cmd file and click on Run as Administrator.It is must to run command prompt with administrator privileges.
- Type SLMGR -REARM (SLMGR is Windows software licensing management tool. REARM command will reset the licensing status of machine) and press enter.
- Now you will see a confirmation window, click on OK.
- Restart your PC.