Windows Vista wants to be reinstalled just to activate

I saw a really odd one today. A Windows Vista (basic) machine suddenly decided that it had to be reinstalled, for no reason. It just claimed that it had to be activated (which it already was) and the only way to achieve this, according to the error message, was to reinstall the entire operating system – which seemed a little like swatting a fly with a bazooka to me.

The actual error message was “windows must be reinstalled to activate. Please insert the Windows CD or DVD to begin reinstallation”.

I guessed there must be an easier way around this, and eventually I worked this out:

1 . When you see that message, press Ctrl + Alt + Del and select “Start Task Manager”.

2. Click the “Applications” tab.

3. Click the “New Task…” button.

4. In the Create New Task window type: iexplore.exe and hit return.

5. Type %windir%\system32 into the browser address bar.

6. Find the file CMD.exe

7. Right-Click on CMD.exe and select ‘Run as Administrator’.

8. Type: net stop slsvc  (it may ask you if you are sure, select yes).

9. Type: cd %windir%\ServiceProfiles\NetworkService\AppData\Roaming\Microsoft\SoftwareLicensing

10. Type: rename tokens.dat tokens.bak

11. Type: cd %windir%\system32

12. Type net start slsvc

13. Type: cscript slmgr.vbs -rilc (This will take a couple of mins to run through, don’t panic).

14. Reboot.

15. You should be presented with a screen telling you that an unauthorised change has been made to Windows and that you need to reactivate. Just type in the product key (usually stuck to the side of your PC) and follow the prompts.

16. Say ‘hello’ again to your fully working computer, complete with all of your files etc.

It was a pain in the bum, so I thought I would share this with you.

Thank you.

**UPDATE** – I saw this again recently and I wouldn’t let me get into the task manager in step 1. To get around this I restarted and went into safe mode (which avoids the error message), and then carried on from step 5.

**2ND UPDATE** – Some people have reported problems carrying out the steps in safe mode. If you have trouble the only alternative is to roll back to a recent restore point (this can be done in safe mode) and if successful this will give you 1 chance to log in to a working version of windows before the error comes back – so use this chance to follow the steps starting from number 5.


  1. Thanks for the fix. To eliminate having to go in to safe mode click on the link at the bottom of the error message that states, “How do I restore ……”. This will bring up the help and support menu. In the search box type “open internet explorer” and click search. About 3 or 4 links down will be a link that says “open internet explorer”. Click on this link. This will take you to a page that displays instructions on how to open internet explorer from the Start Button in Vista. Look above this message and there will be a link that you can click and it will open “internet explorer”. You can then follow the instructions from #5 above. Again, thanks for the fix!!! My problem started with the 0x0000c1f5 and ended with this error. System is up and online. It took me 4 days to crunch it out but it’s done!!!



    • it requires a pneitum 4 with 512 mb of ram. I have it running very fast, faster that 3.6 on a pneitum 3 with 256mb of ram. 3.6 r were only 128 mb of ram. I figured the recommended system requirements would double between 3.6 and 4, but not quadruple. If I had read them before hand I would not have bothered installing firefox 4. I think you are turning off many people by making them so high, and that you did not actually test the minimum system specs but just guessed. You realize that the system specs may be dependent partially on the system specs of the os. So vista and windows 7 will run much higher than xp and 2000, or win9x with kernelx.I am running ubuntu with the light lxde desktop so my system reqirements are lower than someone running it with the default gnome desktop.

      • simonthegeek says:

        Ummmmm…. Kutsia??? I think you might have gone a little off topic there. Are you drunk by any chance?

  2. This activation issue has caused many many headaches, so I want to thank you for this invaluable help!

    I had to roll back to an earlier session (using rstrui) and was then able to carry on from step 5.

    However, I now get a message at the bottom right of the desktop:
    Windows Vista (TM)
    Build 6000
    This copy of windows is not genuine

    !!!!!! Unbelievable! This is a brand new laptop purchased from a large chain of stores…

    If you know how to get rid of that, thank you in advance…


  3. Just after I wrote the message above I found the “proper” way to revalidate Windows in this article:

    All the messages have now gone!

    Thank you again


  4. I had the same problem and I have fixed it using the same thing (cmd…bla bla). Do you have any idea why this type of error occurs so that I will know what to avoid later?


  5. Having this same issue, tried to follow steps but unable to run the slsvc service from within safe mode! And unable to boot into safe mode with networking, any ideas around this, also the vbs script saya acces is denied even though running from admin command proplt, maybe because the service is not running in safe mode?

  6. Shawn Hendrickson says:

    Thanks a lot for the information. I was ctrl-alt-del to work and the services wouldn’t work in safe-mode. You can get to cmd.exe by tapping the shift key until the sticky keys message comes up and then click the link to change it.