I have been having some serious issues with webmail and I can't seem to figure out what exactly is causing the problem. Basically, webmail stops responding, but if you give it enough time it seems to correct itself. The problem is intermittent and may not happen sometimes for days. The OWA box is on DMZ and is separate from the exchange server. I have opened all required ports to both the Exchange box and the DC. Here is the error from the event viewer which pops up at a rate of every minute:
Source:MSExchangeSA
Category:MAPI Session
Event ID 9175
The MAPI call 'OpenMsgStore' failed with the following error:
The Microsoft Exchange Server computer is not available. Either there are network problems or the Microsoft Exchange Server computer is down for maintenance.
The MAPI provider failed.
Microsoft Exchange Server Information Store
ID no: 8004011d-0526-00000000
There don't seeem to be any connectivity issues from the OWA box to either Exchange or the DC. Also, we currently use a Symantec Raptor firewall.
Any help would be greatly appreciated.
Software/Hardware used:
ASKED:
June 9, 2005 1:46 PM
UPDATED:
June 10, 2005 7:24 AM
I have tried all the listed resolutions but none work. I guess I’ll just stick it out until the 2003 Exchange upgrade next month.
I do not use exchange but I have a 2 gateway email servers and 2 sendmail boxes, and when I have logs from the gateway that mention the sendmail box is down, that is because the sendmail box stopped accepting connections, there are thresholds that when reached it shuts down service till it deals with the, anyway you might check performance of the exchange server. maybe give the webmail box some static paths to the exchange server so dns requests are not relied on and it always knows the path. If you are getting hit hard by spammers or haveing some denial of service attack on the webmail server. If you can watch on the exchange server or check its log files at the time of the outages so see what it is logging that may help.
Check to see if you have done any windows update lately. There was an update that microsoft put out last month that disable some communication udp port on exchange server. I can’t remembr what the fix was about. If I find the Notes I will post it.
The update you mean is the KB893066. It caused a lot of problems here too and we removed it to get things working again. Your firewall should protect you from the icmp-attacks.
Did you monitor both server for performance bottlenecks ?
WKR
Nick Dewitte