4 workstations with Windows 10 Pro.
All had worked. Now only one works.
I'm the IT tech. Have checked Port 445 firewall settings, Security and Sharing permissions on the share.
Nothing seems obvious / wrong.
What tests / logs / etc. can be used to help with this?
Since Windows updates constantly and the printer does only when you choose to, the change is vastly more likely to be on the Windows end. Have your IT guy do a Wireshark trace of the scan between MFP and PC and read it to see what the failure is.