As the error descriptions suggests, when the computer tried to register itself with the local master browser (or with WINS) there was a conflict of names as another computer has already registered that name. A quick way to identify the conflicting computer is to use the NBTSTAT command as follows:
This will list the NetBIOS name that the local computer is aware of along with information about name conflicts. Once the name is identified run again NBSTAT:
nbtstat -a computer_name
Between other things, this command will provide the MAC address of the conflicting computer. This MAC address can be traced to identify the workstation. Also, this command may provide the name of the user currently logged in into that computer and if that's the case, it is easier to identify it.
In the case of WINS, there might be a static WINS entry.
Symbolic name: ERROR_DUP_NAME
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