We are running Exchange 2003. Certain hosts sending mail to us will always
cause this event. The odd thing is that the email from some of these hosts
always gets through and the email from some of these hosts never gets
through. I have read the article "How to troubleshoot the "504 need to
authenticate first" SMTP
protocol error". I have read everything I can find on this forum that is
related but I can't find anything that's helpful. If all the messages were
getting through, I wouldn't worry about it but since some are not, I need to
resolve it.
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