Question : UDP Multicast Blocked by XP SP2

Hi,
   I have a client setup on several machines. They listen for Multicast UDP sent on an IP 224.5.6.4 on port 8099. What happens is that machines without XP SP2 get these messages with no problems whereas SP2 machines do not. I have tried disabling the new Windows Firewall aswell as analysing logs and opening up relevant ports but nothing yet. Does anyone have any ideas?!

Kind Regards,
Gareth

Answer : UDP Multicast Blocked by XP SP2

Hmmm...what is the status of the ports?

Try a port scanner.

Here is a nice one:
http://www.foundstone.com/index.htm?subnav=resources/navigation.htm&subcontent=/resources/proddesc/vision.htm