Users trying to activate Windows 11 using Massgraves KMS38 MAS will find that it no longer works as of the latest OS security 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 published 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 the KMS38 method of activation no longer works, as reported by Neowin. The method was deprecated by Microsoft following the November 2025 Patch Tuesday updates. 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.
Via Google, Inet, Massgraves
