HiWe are looking into DR/troubleshooting for our 2003 Exchange environment, and one of the problems mentioned was ifthe transaction logdrive became filled because a client started generating excessive logs somehow (loopy application?).I appreciate this is far less likely than the backups failing and the logs just buildingup, but we have that covered, and I want to ensure we look at allpossibilities.So - let's say aclient *did* start to generate loads of logs.How can I find out, using ESM, which client this is?And - more importantly - is there anyway to I can stop the clientfrom connecting to Exchange? And how about if it is a mobile client connectingvia ActiveSync/Blackberry?

Transaction logs are being generated if any mail transaction happens at Exchange, first step, look in to message tracking that which account is creating problem and if you don't see anything in message tracking log then next step refer below guide to troubleshoot the issue... Troubleshooting Fast Growing Transaction Logs on Microsoft Exchange 2000 Server and Exchange Server 2003 http://technet.microsoft.com/en-us/library/aa996191(EXCHG.65).aspxAmit Tank | MVP Exchange Server | MCITP: EMA | MCSA: M | http://ExchangeShare.WordPress.com

You can make use of utility called EXMON . this one is a great tool to find out which client is generating excessive logs ExMon is capable of showing information such asIP addresses used by clients, Outlook versions and mode (cached mode or classic online mode) , Outlook client-side monitoring data and resource use (CPU usage, Server-side processor latency, total latency for network and processing with Outlook 2003 MAPI clients and network bytes. http://www.msexchange.org/tutorials/Microsoft-Exchange-Server-User-Monitor.html Also take a look @ below article Troubleshooting Fast Growing Transaction Logs on Microsoft Exchange 2000 Server and Exchange Server 2003 http://technet.microsoft.com/en-us/library/aa996191%28EXCHG.65%29.aspx Vinod |CCNA|MCSE 2003 +Messaging|MCTS|ITIL V3|