Ghost Solution Suite

I have GSS 2.5 installed on a 2008 R2 server running WDS. The PCs boot via PXE using a custom Boot.wim that has the ghost client added to it.
All works fine for 1, 2, and even 3 pcs.  However if I go above three PCs the server says the session is in progress but the cleints say waiting on session to start.
I have swapped out siwtches. Staged a brand new server, Tryed Unicast, directed, and multicast sessions.

What am I missing!!!!! Please save my sanity.

Have you Enabled Mulitcast and IGMP for all of your switches between client and the server Computer?

Please see the below document.. I am not sure if your custom boot supports Multicast or not.. But TFTPD32 supports Multicast..

http://www.symantec.com/docs/TECH110312

Let me know if it resolves or helps you

Cheers.