How to restore tokens

1. Type cmd in Start menu.

2. Right-click on the first result (cmd.exe) and click on Run as administrator (confirm by clicking Yes if required).

 
3. Type

 slmgr -rilc
 net stop sppsvc
 cd %windir%\ServiceProfiles\NetworkService\AppData\Roaming\Microsoft\SoftwareProtectionPlatform
 rename tokens.dat tokens.bak
 net start sppsvc

4. Restart your computer 2 times.


* An alternative might be to run "sfc /scannow" (without quotes)