SMTP Service Resets Messages on Restarting


When you restart the SMTP service it is designed to reset the times on the outbound items, as if the messages were just placed into the queue. It does this because it is expected that the SMTP is only restarted if there is a major setting change or a problem, and in this case you want to retry the messages (i.e. if you don't the message may expire immediately or still not be sent for another 3 hours).

In some cases you may wish to change this behaviour. An example would be if there is a very large number of messages in the outbound queue. In this case there is time spent resetting the items when the SMTP service starts.


Changing this behaviour requires the addition of a new Windows registry key as shown below:

For 64bit Windows:

[HKEY_LOCAL_MACHINE\Software\Wow6432Node\Mail Enable\Mail Enable\Connectors\SMTP]

"Reset Messages On Restart"=dword:00000000

For 32bit Windows:

[HKEY_LOCAL_MACHINE\Software\Mail Enable\Mail Enable\Connectors\SMTP]

"Reset Messages On Restart"=dword:00000000

You will need to restart the SMTP service when you change these registry keys. Set the value to 0 to leave the messages untouched on restart or set to 1 to reset the messages (the default behaviour).




Class:HOWTO: Product Instructions
Revised:Wednesday, May 4, 2016