Here it is:

1.Go to „start”.

2.Run-type in „regedit”.

3.Go to „local machine-software-microsoft-windows nt-current version-wpaevents”.

4.Choose „oobe timer” in the rights panel.

5.In the window,delete all the things.

6.Close regedit.

7.Go to start-run-type in „%systemroot%system32oobemsoobe.exe /a”.

8.Choose the second option „use phone to activate”.

9.Click „change product key”.

10.Type in the serial:thmpv-77d6f-94376-8hgkg-vrdrq.

11.Click „update”.

12.Click„remember later”.

13.After that reboot your computer.

14.After restart goto start-run-type in „%systemroot%system32oobemsoobe.exe /a”.

15.It should come up with a message„windows is activated”-finished!

Note:

It works only with windows xp (not with windows vista).