Exchange error

[hizemonster]

We have a new exchange server 2003 and keep receiving the error below: Does anyone have any idea what this error is??



Source:MSExchangeTransport
Category:SMTP Protocol
Event ID:7004


This is an SMTP protocol error log for virtual server ID 1, connection #998. The remote host "66.207.106.202", responded to the SMTP command "xexch50" with "504 Need to authenticate first ". The full command sent was "XEXCH50 2164 2 ". This will probably cause the connection to fail.

For more information, click

http://www.microsoft.com/contentredirect.asp.

 

[Zelandakh]

Check if you are an open relay.
Check if you are on the banned list for emails.
If you are running Symantec AV try disabling it for a short while. (Equally try getting a decent AV suite!).
Anything else in Event Log to help tie it down?