If you see the above prompt when trying to perform an in-place upgrade to Windows 11 24H2, with either a report of one, or both, of:
- This PC's processor doesn't support a critical feature (PopCnt)
- This PC's processor doesn't support a critical feature (SSE4.2)
Then it means that you won't be able to upgrade to Windows 11 24H2, period.
The requirement for modern CPU features is part of critical Windows 11 code, that Microsoft introduced with 24H2 and that
cannot be bypassed.
You should also understand that there's only so much software developers, including myself and Microsoft, want to go to continue to support old platforms, when there exists new feature (in this case new CPU extensions) that can make the software better, and that there has to be a cutting point at which environments that do not support these new features have to be left behind.
The way it works, and this is what Microsoft did, is you announce public system requirements (which, in the case of Windows 11, officially required using a modern CPU with PopCnt and SSE4.2 from the very first release), while still providing an
unofficial "grace period", during which you
might be able to apply bypasses to continue to run the software on hardware that does not meet these requirements... until the day where the software developer enforces them. And 24H2 is when they made the requirement for a CPU that supports PopCnt and SSE4.2 come into actual effect.
In short: You shouldn't expect to be able to run Windows on hardware it wasn't designed for forever. You got granted the ability to do so for a few years, but it should be obvious that this was always going to end
eventually, and that, at some stage, you do have to upgrade your hardware to benefit from modern features (most of which aren't simply "gimmicks", but elements that actually improve the software).
And,
no, Rufus can not
magically add bypasses that'll work around these restrictions.
