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Agreed. You could also try temporarily disabling the firewall on both PCs to see if that's the block, just remember to turn it back on.

Yeah, Ah, got it, the G4560 is the issue—it's not on Microsoft's supported CPU list for Windows 11.

+1 You could also run the Windows Update Troubleshooter first, as it can sometimes clear up the kind of issues that cause that error.