I keep getting these errors in my event log. I applied the SuppressExternal registry hack, and turned the logging down to minimum. I don't understand. It seems that mail flow is functioning these days, but I wonder how concerned I should be about this: This is an SMTP protocol log for virtual server ID 1, connection #233. The client at "126.96.36.199" sent a "xexch50" command, and the SMTP server responded with "504 Need to authenticate first ". The full command sent was "xexch50 1008 2". This will probably cause the connection to fail. Followed most of the instructions in this KB article: http://support.microsoft.com/default.aspx?scid=kb;en-us;843106&sd=ee I'm not sure how it is possible to raise the elevation of privileges for the xexch50 command.... -Jason The HealthCare Chaplaincy is a multifaith community of professionals from many cultures dedicated to caring for persons in spirit, mind, and body. We are committed to excellence and leadership in pastoral care, education, and research. Privileged/confidential information may be contained in this message. If you are not the addressee indicated in this message (or responsible for delivery of the message to such person), please notify the sender and do not copy or forward this message to any other person.