When your Exchange Server's Message Transfer Agent (MTA) logs a fatal error (an event log error with a severity level of 16), the agent is designed to try to recover from the error and then attempt to shut itself down cleanly. If the MTA cannot shut down cleanly, it may "hang" and require you to kill its process.
When you have to kill the process, the MTA doesn't write other significant events that could help explain why the crash occurred to the event log. If you're having a problem with persistent and unexplainable MTA crashes or hangs, you may want to temporarily suspend the MTA's ability to recover from a fatal error. Doing so will cause the MTA to shut down immediately when it encounters a fatal error. If you've configured Dr. Watson as your default debugger, it will capture the MTA's dump information to user.dmp, and you can use this info for debug analysis.
To suspend the MTA's ability to recover from a fatal error, you must make a registry change.
- Start Regedt32 and open the key HKEY_LOCAL_MACHINE on Local Machine.
- Open SYSTEM/CurrentControlSet/Services/MSExchangeMTA/Parameters.
- Choose Add Value from the Edit menu.
- In the Value Name field, enter Raise Exception On Fatal Error.
- In the Data Type box, enter REG_DWORD.
- Click OK and enter the value 1 in the Data field.
We recommend that you use this registry setting until you've been able to successfully troubleshoot your MTA problems and then set the value of the key to 0 when your system is stable. This will allow the MTA to try to shut itself down if a different fatal error occurs.
This Exchange tip comes to you courtesy of our TechMails e-mail newsletter service. Click here to sign up for our Exchange tip , or check out our entire selection of daily and weekly tips at the TechMails home page .