I have a school mail server on a Centos 4.2 box that has been running fine
for almost a year. We haven't made any changes on it for many months.
Today I got a call from a staff member saying no one could retrieve or
send email.  We relay the mail to this server after scanning for spam.
Nothing has been changed on that server either. Messages sent to their
domain get bounced back from our relay server with the following info:

  ----- Transcript of session follows -----
... while talking to [x.x.x.x]:
>>> DATA
<<< 550 relay not permitted
550 5.1.1 <firlev at domain.com>... User unknown
<<< 503 valid RCPT command must precede DATA

This happens for every user.

Their log file only shows pop3 logins.

When I attempt to restart sendmail I get:

Failed to start sendmail :
Starting sendmail: [  OK  ]
Starting sm-client: exim abandoned: unknown, malformed, or incomplete
option -L
[FAILED]


Any idea what to do here?

Raymond

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