Hi CSP,
Have a look at this link as see if it points you to the right solution...
https://forum.support.xerox.com/t5/Copying-Faxing-Scanning/WorkCentre-6515-error-018-755/td-p/212993
I am getting the error message 018-755: Servier connection error in SMB when I try to scan to my desktop. This is the third time we've had this issue for no apparent reason. PLEASE HELP.