Navision network broadcast

Hello everyone,

we have a little problem in our company with Navision. We use (Client) Navision Attain 3.60 on Win2000 Terminal Servers with Citrix MetaFrameXP. The Navision Server is with MS SQL2000 Server on a Win2003 Server.

We noticed that after an user opens Navison on the TerminalServer the Terminal Server makes network broadcasts (some every second) even the users doesn’t do anything in Navision. And this network brocasts multiply with every more user on the Terminal Server.

Here are some details of these network broadcasts packets/frames:
Source IP: IP address of the Terminal Server
Source port: 45179 - (45197)
Protocol: 17 (UDP)
Destination port: 45178
Destination IP:
Readable data in the packet: ANNOUNCE\TS001\4724\2995\2.0\user1\\Department - Microsoft Navision Attain

I checked the Navision Server and there is no listen port or communication with port 45178. I have no idea why Navison does that and how to stop that.

Please can someone help or has an idea?