Before

Open a DOS command prompt, and type netstat -a. Under the 'Local Address' column, look for services with names that start with 'nb': 
C:\>netstat -a
Active Connections
  Proto  Local Address          Foreign Address        State
  TCP    geezer:nbsession       dsl-212-144-196-225.arcor-ip.net:1025  ESTABLISHED
  UDP    geezer:nbname          *:*
  UDP    geezer:nbdatagram      *:*
Here we see some vermin connected to the NetBIOS port of my computer while I am dialed in to the Internet.

The fix

Delete the Win95 NetBIOS-over-TCP driver. From the commad prompt, type: 
c:
cd \windows\system
del vnbt.386
It may be necessary to restart Windows for this change to take effect.

After

C:\>netstat -a
Active Connections
  Proto  Local Address          Foreign Address        State
(Type EXIT to close the command prompt window.)

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