Hello Joerg,

Windows used my Linux-based DNS to do name resolution (which works fine, btw). So, what exactly is a Master Browser and how do I find out which > of my machines is it ?

Is there a Windows-Servers acting as PDC (primary doamin controller) in your network available ? Instead you samba-running linux box played that role, maybe .. ? The master browser is this machine which "scans" the network for win-boxes -- to explained it very simply. Please don't wrap together windows-name-resolution and (your Linux) DNS. Windows use WINS as default and can be configured only to use DNS as backup.

nbtstat -r yields only a few of my machines.

This exactly shows your problem which your WINS Try to check if all Win-Boxes are set to use you linux box as "master browser" Star with the autoupdated XPs fist ;o) HTH Kris