I’ve been having tons of problems with a new Windows 2003 SBS R2 server’s Exchange. This small office of four users have had terrible problems sending email intermittently. It’s bizarre, users can email people one minute, then they get 5.7.1 NDRs the next, saying relaying denied. One user even got this message trying to email me at my corporate account, while the other’s could send to me with no issues… then the problem mailing me just magically went away, but it seemed to migrate to other domains (but not all users in those domains!).
I changed them over to a static IP address, got the reverse DNS PTR record setup for their mail server, but the problem persists. The only thing I can think may be the problem is they are setup to send and receive mail for two separate domain names – maybe something’s messed up in the SMTP connector.
Anyway, I wanted to post about some of the troubleshooting tools I’ve used during this saga. Most will be familiar to many readers, yet I usually forget they exist and have to rediscover them every time a SMTP problem arises.
The first thing I did was enable maximum SMTP diagnostic logging per KB265139 in Exchange System Manager. While this provided me extended details, I eventually enabled the registry setting which enables field engineer level logging. To do this, set the following registry value to 7:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchange Transport\Diagnostics\SMTP Protocol
After enabling the field engineer logging, I downloaded ExchDump and ran it using the /smtp option, which will dump all of your Exchange server’s SMTP configuration into an .htm and .xml file.
ExchDump provides just an overwhelming amount of information, so I used XML Notepad 2007‘s Diff feature to compare the .xml file from the problem server against an .xml file I created using ExchDump on a working SBS 2003 Exchange server.
To find the differences between the two .xml files using XML Notepad 2007:
1) Load the first .xml file
2) Select View – Compare XML Files
3) Select the second .xml file
You’ll see both files side by side, with the differences highlighted. You’ll also find handy links that will take you to the next/previous difference found in the files.