Client for Windows - in-place upgrade from Win 10 to Windows 11

I have customer, which is doing in-place upgrades from Win10 to Win11. It's out of discussion, that this approach is not the best.

He did many of upgrades ( 10 + at least ) and only on one workstation he got troubles. NSS drives can be mapped, but are super slow when opening folders and/or opening Office document. Problem aren't limited to OES client, worse situation is with Samba drives, which can't be mapped. 

Anyone faced this situation ? 

Thanks for hints.

David