You probably know that you can reset the grace period up to three times with the command slmgr -rearm. This "rearming" allows you to run Vista without license key up to four months. It seems that Brian Livingston has found a method to prolong this period indefinitely using the SkipRearm registry setting.

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One only has to change the SkipReam registry subkey to 1. You can find this key here:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurentVersion\SL

Then, you run slmgr –rearm on a command prompt with administrator privileges before the grace period is over. This will give you another grace period of one month. According to Livingston, this can be done for an indefinite number of times if SKipRearm is set to 1. In his tests he was able to rearm Vista 12 times. He writes, however, that it didn't work with a full version of the Home Premium edition.

Note that it is not a dirty hacker trick. Microsoft recommends this in a Technet paper if you have to run sysprep more than three times. I don't know, why one should run sysprep more than three times, but this can be very useful if you have problems activating Vista. SkipRearm is a documented parameter which can be used during an unattended setup. Here is an example how to use it in unattend.xml.

This is very strange, if it is really true. Why is Microsoft imposing this hassle on us if the bad guys can use Vista without activation, anyway? This Computerworld article contains kind of a reaction from Microsoft. David Lazar, the director of the Genuine Windows program says:

It is important to note that these hacks are, at best, temporary. Microsoft has systems in place to detect and block piracy.

Well, I guess this won't be the last time we'll hear about such "hacks".

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Update: Microsoft denies that the Skiprearm hack works.

  1. Avatar
    labtroll 17 years ago

    quote: [It is important to note that these hacks are, at best, temporary. Microsoft has systems in place to detect and block piracy.]

    That’s assuming people using this “hack” will update windows all the time.

  2. Avatar

    I think they know that they never really can block piracy. The only question is if they can earn more with WGA. This “hack” is kind of a backdoor for Microsoft. It allows them to pacify the anger of corporate customers. I guess they are testing now how far they can go.

  3. Avatar

    /nul, thanks for the link. I just posted another article about the Skiprearm hack.

  4. Avatar
    shahid roofi khan 16 years ago

    skiprearm flag is flag for audit mode image of vista. It’s actually intended to bypass the limit of 3 time sysprep possible otherwise. But remember when you are in skiprearm=1. You are already in illegal state of vista, such a copy can easily be detected, because no such copy is supposed to be running in production !

  5. Avatar
    asyncritus 14 years ago

    I used one time the skip-rearm and after one month of grace period I try to used it for the second time but it doesn’t work anymore. I try to do it many times the same procedure the way I do it in the first time but nothing change. My personal laptop has previously formatted to genuine vista premium, can I used again the original registry number of my vista premium if ever I decided to reformat again this lap top to vista premium or but I love ultimate vista. I used one time the registry number of premium vista to ultimate vista but it doesn’t work. Is there anyway to change this validation key and used it to vista ultimate instead.

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