A problem I would be grateful for some help on
For the last couple of weeks we have had exchange stop sending outgoing messages and issue non delivery reports as below.
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<XXXXX.co.uk #5.5.0 smtp;550 won't relay to XXXXXXXXX>
I have checked the smtp queue and the messages are stuck there with no message showing in the box at the bottom. When I use force connection it goes down slowly.
Exchange is set to "always run"
There is nothing in my groupshield or virusscan logs or event viewer
One clue is it has happened just after i sent about twenty emails that could look like junk. It happened the same time the week before. I have tried to disable the intelligent message filter by selecting "take no action" on detected items. I do not know how to stop the filtering altogether and whether it filters outgoing mail too.
Restarting exchange clears it all and gets it working until the next time
I have attached screen print of the message queue / tracking.
One thing I have noticed is the internet connection wizard and connector shows outgoing smtp server as londonmail....... whilst screenprint shows mail...... however 98% of all emails go through fine its just it sometimes queues and issues NDR.
I have just noticed noticed this "connection was dropped due to an smtp event sink" on the exchange queue. I also get this error in the logs
Event Type: Error
Event Source: DCOM
Event Category: None
Event ID: 10009
DCOM was unable to communicate with the computer mail.XXX.co.uk using any of the configured protocols.
For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp
Any help appreciated!!!!!