Massgrave confirms KMS38 activation method has been deprecated by Microsoft as of the latest Windows 11 updates

With Windows 10 reaching the end of mainstream support last month, many are taking a hard look at Windows 11. But those looking to activate the operating system without a license have one less option to do so. Microsoft has blocked an activation method known as KMS38 that allowed people to activate Windows illegally.

The tool in question comes from a group called "Massgrave." The “MAS” in the name stands for Microsoft Activation Scripts. That group publishes a set of tools online that allow you to activate Windows and Office without a license. The PowerShell scripts are available on GitHub and let users run Windows or Office without paying any fees.

The author of Massgrave confirmed that one method known as KMS38 no longer works, as reported by Neowin. The method was deprecated by Microsoft following the November 2025 Patch Tuesday updates, but other activation scripts from Massgrave continue to work.

Ed Bott discussed the tools earlier this year for ZDNet and performed extensive testing. Back in February, he was able to use Massgrave's scripts to activate a PC and grant that system three years of Extended Security Updates.

Bott had similar success activating Office with the tools shared by Massgrave. It's difficult to determine how safe the tools are, even if they are effective. Even if the scripts shared by Massgrave are entirely safe, bad actors could distribute modified, malicious versions.

Earlier this year, we saw a malware-filled copy of a tool used to bypass Windows 11's minimum requirements. That's just one example of bad actors copying a tool and infusing it with malware.

If this all sounds too good to be true, that’s because it is — at least for those who care about legality. Massgrave is open about the fact that its tools are for piracy.

While detection by Microsoft isn’t guaranteed — or even likely in most cases — there’s still a risk of being caught using the tools. Businesses in particular could run into issues if their IT teams used Massgrave to activate PCs and use unlicensed software.

Plugging holes

Usually, I'm one to speak out against Microsoft blocking workarounds. I'm frustrated by the dwindling options to set up a Windows 11 PC without the internet or a Microsoft account. Microsoft blocked a popular bypass of those requirements earlier this year, much to my chagrin.

But the situation is different for MAS, which is often used to activate Windows illegally. It's reasonable for Microsoft to take steps to stop MAS from being able to activate Windows without a license.

Some may not be so eager to use Windows 11 if it requires a full license. While people have joked about every year in recent history being "the year of Linux," we may actually see an exodus of Windows users to other platforms following the death of Windows 10.

Because of the minimum requirements of Windows 11, many PCs cannot be upgraded to the new operating system. Linux and Google's ChromeOS are more viable options than ever due to advancements on both platforms. Some have even gone so far as to make WINUX, a free Linux distro designed for Windows users.

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