MSN Messenger uses TCP port 1863. So you will need to:
•Define a Service Definition for MSN Messenger
•Define a Packet Filter Rule to Deny MSN Messenger
•Enable the Packet Filter Rule
In Definitions->Service, create a new Service Definition as:
Name=MSN_Messenger_Text
Type=Service
Protocol=TCP
Source=1:65535
Destination=1863
Comment=MSN Messenger Text Chat
Click "Add Definition"
In Packet Filter Rules, create a new Packet Filter Rule as:
Position=Top
Source=Internal Network
Destination=Any
Service=MSN_Messenger_Text
Action=Deny
Comment = Blocks MSN Messenger Text Chat
Click "Add Definition"
Now enable the newly created rule, as by default, all new rules are disabled (click on the traffic lights changing red to green).
