Following the instructions here, I have installed a Samba print server on an ARM-based Udoo-quad running Udoobuntu 12.04 LTS.The Samba server is working, and (after setting guest ok = yes in the server's smb.conf) I can browse the print$ (Printer Drivers) folder without entering credentials.  I am able to browse to the printer during client-side printer installation (on Ubuntu 13.10), but print jobs do not make it to the server.  They just sit in the client print queue with the status message Held for authentication.I have the server configured to allow guest access to printers with the following section in /etc/samba/smb.conf (as reported by testparm):[printers]    comment = All Printers    path = /var/spool/samba    create mask = 0700    guest ok = Yes    printable = Yes    print ok = Yes    browseable = NoWhy does the client think that authentication is required, and what is the fix?
Print job Held for authentication
ubuntu;samba;printing;arm
Apparently, this is a problem/complication that was introduced in the version of Samba included in (at least) the initial release of Ubuntu 12.04.  I don't know if there was an update for 12.04 to fix this -- updates don't appear to be available for Udoobuntu.I resolved it by following Comment #17 from the launchpad bug acces denied samba printer shares after upgrade precise.Excerpt from server's smb.conf:[global]   map to guest = bad user########## Printing ##########   load printers = yes   printing = cups   printcap name = cups   use client driver = yes[printers]   comment = All Printers   browseable = no   path = /var/spool/samba   printable = yes   public = yes   guest ok = yes   read only = yes   create mask = 0700The consensus seemed to be that the key was use client driver = yes.