Can you give some more info on your network? How many computers are connecting to the Lytec software through the network, what computer you use for a server (including operating system and hardware specs), whether the Linksys router you use is a home-use $50 dollar version or a very nice small business version, if you have the Linksys router or your server doing DHCP? These are things that will need to be known to start troubleshooting.
(The following is from Bert's advice to me, and I am now in strong agreement)
For the best and most concise help, please think of trying
http://www.experts-exchange.com . They have a free trial, and the people there are experts in many things related to the trouble you are having. I am about 99% sure that the problem lies in the way your network is setup.