This is spooky. We have the EXACT same problem. We are using FMP server 5.5 running on an OS 9 machine and have 10 machines, all on OS 9 logged in and they never, never, ever, like in years, lost communication. We have one OSX machine that loses communication after approx. 5-6 minutes of inactivity, even if it is running OS9 under classic. I am going to try to change the server to OS X and run the FMP Server 5.5 under OS X and see if that makes any difference. Any suggestions?