A client has a SBS 2003 SP2 box with Exchange 2003 (6.5 SP2). Also installed is Symantec Protection Center and SIFMSME (version 220.127.116.112). A couple of months ago they moved offices, new static ip, so just changed mx records and we were up again. Whether related or not, a few week after that, they noticed no emails coming in. Client would restart server and all running again. It has sporadically happened 3 times in last month. Now, "they say" they are receiving emails sporadically. Looking at event viewer, all I see is alot of Warnings on "Event 236 -Quarantine limit has exceeeded"; a few on Event 3033, Source - Server ActiveSync "The average of the most recent hearbeats...". Also a few Error message from MSEXchange Transport, Event 7515 "An error when Exchange Intelligent Message Filter attempted to filter...". There might be a couple more...will write down shortly. Which direction would you start to troubleshoot? Thx for your help.