On Tuesday, Microsoft published the final version of its next major Windows 11 upgrade (22H2) to Release Preview testers, inadvertently making it available to PCs that weren't officially supported. Oops.

Hundreds of Windows Insiders were able to upgrade their Windows 10 workstations on older CPUs thanks to a mistake discovered by Twitter and Reddit users (via WindowsLatest).

Because Microsoft's Windows 11 has tight minimum hardware requirements, millions of PCs will be left behind, the error will once again expose the company's divisive upgrading strategy.

With very few exceptions, Windows 11 requires Intel 8th Gen Coffee Lake or Zen 2 CPUs or above.

While there are simple ways to install Windows 11 on CPUs that aren't supported, Microsoft doesn't let.

Its Windows Insiders install beta releases of the operating system on incompatible PCs, so this error is unusual.

Microsoft is aware of the error and says it is looking into it. The official Windows Insider Twitter account says, 'It's a bug, and the right team is looking into it.'

If you installed Windows 11 on an unsupported PC and were only expecting Release Preview updates for Windows 10, you should be able to undo the upgrade in Windows 11's settings area.