We are having issues with people in other domains which we have trust setup between sending duplicate emails out. I wanted to know what best practice for setting up these types of scenarios is.
The errors are:
This is an SMTP protocol error log for virtual server ID 1, connection #5249. The remote host "172.x.x.x", responded to the SMTP command "xexch50" with "504 Need to authenticate first ". The full command sent was "XEXCH50 1848 2 ". This will probably cause the connection to fail.
It doesn't actually fail, it just sends the emails twice occasionally.
Any suggestions would be appreciated, thanks!