New version of Windows 11 Pro is about to break whpx support in winevdm

[dcharlespyle]

I just received earlier this week the latest update of Windows 11 Pro in the Beta channel and found that all apps using whpxvm support in winevdm hang at their startup screens. This continues until the ini file line vm=whpxvm.dll for the hypervisor either is switched to vm=vm86.dll or is commented out. Windows build is 24H2 26120.3576. When that hits general release, it is likely to break a number of installations of users using winevdm. I have tried all sorts of things, including use of overrides and exceptions for otvdm.exe and otvdmw.exe, to no avail. Just letting people know what is coming around the corner. Everything has been working great in winevdm until this week.

[cracyc]

I just got 26100.4061 and see something like this problem. It does run for me but extremely slowly, much slower than the emulation.

[dcharlespyle]

I just got 26100.4061 and see something like this problem. It does run for me but extremely slowly, much slower than the emulation.

I watched and waited, and after a while, the start screens of the applications began to appear, but very slowly. So, it seems to be related. But whatever it is about the newer versions of Windows, I have no idea at the moment.