I received the following message in my NT 4 Server Event Viewer:

The master browser has received a server announcement from the computer
DELL_WKS that believes that it is the master browser for the domain on
transport NetBT_CpqNF31. The master browser is stopping or an election is
being forced.

Since this message appeared, the users were unable to log-in to the
Server.
I guessed that it is the DELL_WKS (loaded with NT 4 Workstation) is
giving the problem. How can I default the main NT Server to be the
Master Browser, rather that automatically granting any powerful workstation
to be the Master Browser? Pls advise, thank you.