SkipRearm doesn’t work, activation still broken

Brian livingston By Brian Livingston

In a Mar. 15 article, I reported that a Registry key called SkipRearm seemed to allow Windows Vista’s activation deadline to be pushed back many times.

It now appears that this effect isn’t caused by SkipRearm but by a different mechanism — and therein lies a story.

Vista activation deadline affected by system clock

Since my original article appeared, some readers and blogs reported that they could duplicate the results of changing the SkipRearm value in the Registry. Others found no effect on Vista’s activation deadline.

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My continued tests have convinced me that SkipRearm cannot be used to extend Vista’s deadline. Instead, the results indicate that Vista has something I call “defensive mode.” In this mode, Vista changes its activation deadline if a PC’s system clock is changed.

Try the following steps on a fresh copy of Windows Vista:

Step 1. Install Vista on a clean hard drive.

Step 2. When prompted for the correct time by Vista, set the clock back at least a few minutes from the original time held by the system clock. Or set the clock back at any point after you’ve installed Vista.

Step 3. Open a command window with admin privileges. To do this in Vista, click the Start button, enter cmd in the Search box, and press Ctrl+Shift+Enter. If you’re asked for a username and password, enter the ones that log you into your domain. At the command prompt, type slmgr -dli and press Enter. This command, which can require as long as one minute to process, displays Vista’s license information. Note the number of minutes remaining before Vista’s activation deadline. It’s a maximum of 43,200 minutes (30 days) on a new installation. Type exit and press Enter to close the command window.

Step 4. Reboot the PC, then repeat step 3 to determine the new number of minutes remaining.

On the PC’s we’ve tested, Vista’s activation deadline has been pushed back a seemingly random amount of time by this procedure. We’ve seen changes of as much as 303 minutes (more than 5 hours). The process has nothing to do with the SkipRearm key in the Registry and doesn’t allow SkipRearm to push the deadline back indefinitely. This means dishonest PC sellers can’t use SkipRearm to create PCs that look activated but aren’t, as I had feared.

In our extensive tests of Vista, which I worked on with WindowsSecrets.com program director Brent Scheffler and associate editor Scott Dunn, we believed that the rollback of the activation deadline we saw was being caused by SkipRearm. We repeatedly wiped different PCs clean, installed Vista (and reset the clock each time), tweaked the SkipRearm key, and then rebooted. In most cases, after the Registry change and the reboot, the deadline shifted all the way back to 43,200 minutes because our latest clean install of Vista was only a few minutes old. We now believe that Vista’s “defensive mode” changes the deadline, not SkipRearm’s value in the Registry.

Vista seems to have built-in defenses against a user setting a PC’s clock, say, 10 years into the future, installing Vista, and then changing the clock back to the present to get more than the official 30-day activation period. When Vista notices that the clock has changed, it saves information about the original time and the new time upon shutdown. Vista then rewrites the activation deadline to preserve what’s left of the 30-day grace period.

Since Vista cannot know how long a PC will be shut down before it’s booted up again, the operating system appears to be programmed to add a random amount of time to the deadline. The additional minutes are apparently intended to make sure the user gets the full 30-day grace period, without the reboot time counting against it. That’s very considerate of the developers who coded this feature into Vista.

Never mind, Vista activation cracks are everywhere

At the time of my original findings, I considered the SkipRearm side-effect to be a glitch, a temporary programming error that would eventually be reduced to a footnote by some Microsoft corrective patch.

As it turns out, the SkipRearm value in the Registry truly is benign, but not because of anything Microsoft has done. Instead, hackers have found that Vista’s activation mechanism is full of holes. A query in any search engine on vista activation crack reveals numerous successful breaches of Microsoft’s defenses. These range from downloadable executables that effectively stop Vista’s countdown timer to brute-force algorithms that rapidly enter 25-digit license keys at random until a legitimate one is found. (I’m not linking to these techniques because I don’t recommend that anyone use them. But it’s indisputable that they’re out there.)

Once again, Microsoft has launched a copy-protection system that is a breeze for hackers to break, while causing headaches for honest, paid-up buyers. To deploy Vista, large companies are exhorted to administer cumbersome license systems, such as Microsoft’s Key Management Service (KMS) server. Meanwhile, hackers publish spoofed software that easily emulates such servers, as reported by Gregg Keizer in an InformationWeek article.

We can’t do much about Microsoft’s executive decisions now. But we can continue to educate ourselves about Microsoft Windows and its foibles.

Fortunately, all of the other tricks we’ve recently printed about Windows Vista still work just fine:

Vista Upgrade accepts itself as a qualifying version. Developers within Microsoft decided that the cheaper, “upgrade” version of Vista would install over itself, eliminating the need for users to buy the more expensive, “full” version. I reported this in a Feb. 1 story.

Use Vista without activation for 120 days. Far from being limited to a 30-day grace period, the Vista team built into the new operating system a simple command that anyone can use to push the deadline back to 120 days. I published the technique in a Feb. 15 article.

I’ll keep digging up the secrets of Windows for you and publishing them here, with your help and the assistance of my talented co-workers. I won’t always get the story right the first time out, but I promise you that I’ll always keep trying.

Brian Livingston is editorial director of WindowsSecrets.com and the co-author of Windows Vista Secrets and 10 other books.
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All Windows Secrets articles posted on 2007-07-05: