I'm a programmer, not a system adminstrator, so please forgive my administrative naivete. My software, written in C#, relies on UDP multicasting. One machine, the server, streams events to an known UDP group address (configurable, but 22.214.171.124 by default), to which all of the clients on the network are subscribed.
Usually this works great, but at some of my clients it does not work at all, and often their network administrators are unable to fix the problem. My question is, on a Windows network, what would the common causes be for UDP multicast not working? Is there anything I can tell the network administrators about how to fix it or at least where to look?