I have a front end back end Exchange topology running on Server and Exchange 2003. Front end is running on an MS Virtual system, and both Exchange servers are running on Windows 2003 servers. I recently implimented OWA, and every so often my front end loses connection to one of the Exchange servers. The front end retains the connection to the back end server that resides on the same network but drops the back end that is on a different network connected via a PPP WAN connection.I ran httpwatchon an account that was on the back end that the connection was lost to, and it times out on retrieving themailbox. This is the line it times out on: 00:00:29.5520.1555247242GET200text/xmlhttps://XXXXXXX.com/exchweb/6.5.7638.1/controls/tf_galfind.xsl A reboot of the effected Exchange server or the OWA front end fixes the problem temporarily.I recall researching this and remember seeing a hotfix for Exchange but I couldn't get access to the hotfix because we didn't have Exchange 2003 listed under or support contract. Has anyone run across this issue? Thanx

I would suspect that is caused by thewindows2k3 sp2. please see the following article post on my blog. http://cybernetcoffee.spaces.live.com/blog/cns!FB8C479E6972D758!281.entry

I actually don't have SP2 installed on this particular server. The network driver version is 5.5, using the generic Intel based adapter that Microsoft Virtual Server utilizes. Another thingI found was it actually doesn't take a reboot to fix, simply resetting the NIC fixes it as well. Butthe problem is still poppingup intermittently.Could there be something else causing this connection to drop? When it is down I can ping all the Exchange back ends by name, but the OWA front end won't connect the users who have thier mailboxes on the back end thatis located remotely. The locally connected back end works fine. And it looks like authentcation works fine as well. Thanx

I actually dont have SP2 installed on this server. The network driver is at version 5.5, using the generic Intel based driver that Microsoft Virtual Server utilizes. One thing I need to add to my first post is that it doesnt really take a reboot to fix. Simply resetting the NIC fixes it temporarily as well. But the problem is still popping up sporadically. There is nothing in the event logs referencing any problems. When the connection to the offsite back end drops I can still ping it from the front end and the local back end works fine. But anyone who has their mailbox on the offsite back end cant retrieve their mailbox in OWA. It looks like their user authentication is working but we have DCs locally connected as well. Thanx