Check the contents of the message and the "Subject: ".  In worst cases, it could be an autoresponder war.

This could be triggered by an Out-of-Office message -- some autoresponders reply to every address they can find in the mail (From:, Sender:, etc).  We use office 365 and have blocked our mail system from responding and I use the content filter to block outside senders as well.   

________________________________________
From: LISTSERV Site Administrators' Forum <[log in to unmask]> on behalf of Mills, Douglas <[log in to unmask]>
Sent: Wednesday, January 4, 2017 2:50 PM
To: [log in to unmask]
Subject: User Consistently Being Served Out

I’ve been working with a user who seems to be constantly being served out and from my understanding, this is often a result of the emails being sent being parsed as a command that ListServ couldn’t understand (i.e. https://answers.syr.edu/display/itsservapp011/Why+is+user+served+out)

However in reviewing the our SMTP logs, I’ve confirmed the message she was trying to send to the subscribers of that list that failed was the only one she had sent since the last time this issue occurred and I had issued the SERVE command respectively.

Unfortunately, there isn’t much else in terms of documentation to help pinpoint what is causing her account to be served out, so I was curious if you guys had any leads on how I can locate what’s happening with this user so it can be prevented.

Thank you in advance!
Douglas E. Mills

________________________________

To unsubscribe from the LSTSRV-L list, click the following link:
http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1

############################

To unsubscribe from the LSTSRV-L list:
write to: mailto:[log in to unmask]
or click the following link:
http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1