are you using a 92xx ? if yes, thats a know bug
contact xerox to obtain the last firmware release : 061.0x0.222.10002
its not listed on the site so you need to call
Xerox ColorQube -> Workflow Scanning
We receive the error “The selected job request cannot be supported.” when trying to use workflow scanning.
It doesn't even let you try to scan.
We've compared this printer to other ColorQubes and all the settings appear to be the same.