Error code

Windows ERROR_DUP_NAME

WINDOWSERROR_DUP_NAME
System Error Code· A POSIX/system errno returned when a system call fails.

What it means

You were not connected because a duplicate name exists on the network. If joining a domain, go to System in Control Panel to change the computer name and try again. If joining a workgroup, choose another workgroup name..

How to fix it

  1. Rename one of the conflicting computers in System Properties.
  2. ensure each machine has a unique computer name before joining.
  3. flush the NetBIOS name cache with 'nbtstat -R'.
  4. reboot after changing the name.

Not affiliated with Windows. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.