Just had an error with robocopy using the /B flag and had to change it to the /z flag because of these errors when trying to copy to the mapped unc path (with drive letter).

net use * "\\BLAH\NESTED\OBFUSCATED.WITH SPECIAL_CHARS\SHARE\NAME\DOWN
+\DEEP"
-----
Drive Z: is now connected to \\BLAH\NESTED\OBFUSCATED.WITH SPECIAL_CHA
+RS\SHARE\NAME\DOWN\DEEP.

ROBOCOPY "C:\Users\SERVICE_ACCOUNT~1\AppData\Local\Temp" Z:\ Crap.csv 
+/B 


----------------------------------------------------------------------
+---------
   ROBOCOPY     ::     Robust File Copy for Windows                   
+           
----------------------------------------------------------------------
+---------

  Started : Fri Oct 12 11:12:23 2018

   Source : C:\Users\SERVICE_ACCOUNT~1\AppData\Local\Temp\
     Dest : Z:\

    Files : Crap.csv
                    
  Options : /COPY:DAT /B /R:1000000 /W:30 

----------------------------------------------------------------------
+--------

ERROR : You do not have the Backup and Restore Files user rights.
*****  You need these to perform Backup copies (/B or /ZB).

ERROR : Robocopy ran out of memory, exiting.
ERROR : Invalid Parameter #%d : "%s"

ERROR : Invalid Job File, Line #%d :"%s"


  Started : %hs

   Source %c 

     Dest %c 
       Simple Usage :: ROBOCOPY source destination /MIR

             source :: Source Directory (drive:\path or \\server\share
+\path).
        destination :: Destination Dir  (drive:\path or \\server\share
+\path).
               /MIR :: Mirror a complete directory tree.

    For more usage information run ROBOCOPY /?

                                                          
****  /MIR can DELETE files as well as copy them !

net use Z:\ /delete 

Z: was deleted successfully.
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