How to activate your windows 7 with out activation key

1. open command prompt ( start – allprograms – accessories – right click on command prompt – select Run as adminstrator  )
2. type slmgr –rearm

Note: there is aspace between “slmgr and 

the hyphen  

3. strike Enter key
4. After restarting the computer, the windows updated to 30 days.

a

  Note: this step works for only three times