JSI Tip 4384. Windows XP user name may not be the same as the computer name?

Windows XP implements a check to prevent you from creating a user name that is the same as the computer's name.

This will prevent problems with programs that use NetBIOS names from mistaking an 03 NetBIOS entry (user), from a 03 NetBIOS entry (the computer's Messenger service).

If you open a CMD prompt and type nbtstat -a , a display similar to the following is produced:

Local Area Connection:Node IpAddress: [nnn.nnn.nnn.nnn] Scope Id: []           NetBIOS Remote Machine Name Table    Name                 Type        Status    ---------------------------------------------    SERVERNAME     <00>  UNIQUE      Registered    DOMAIN         <00>  GROUP       Registered    SERVERNAME     <03>  UNIQUE      Registered    SERVERNAME     <20>  UNIQUE      Registered    DOMAIN         <1E>  GROUP       Registered    USERNAME       <03>  UNIQUE      Registered    MAC Address = 00-B0-D0-DC-E5-87

where:

00 is the Workstation service.

03 is the Messenger service.
03 is the user name. 

20 is the Server service.

Notice how a duplicate user name and computer name would both register identical 03 entries.