3.16 64bit install error on registering shell with Windows 11 Insider Preview (Dev Channel 25126, 25136, 25140, 25145, 25151, 25158, 25169, 25174)

OK, thanks for checking!

Have you also reported that to Microsoft? I've also checked with the Beta version 22621.1 which still works as expected.

Edit: I've reported the issue via Feedback Hub to Microsoft at https://aka.ms/AAh7fez.

If you're on the Dev Insider channel, it would be great if you could upvote the feedback so that it gets some attention. From what I see, only very few Win32 apps do support the new Windows 11 context menu via a sparse package yet, so I suspect, very few others would report that.