That looks like a spam rejection from the recipients email system. I believe it is saying that your email server has been designated as sending spam. The fix is probably on the recipients end.
Easiest fix for a non technical user is to subscribe with an alternate gmail address.
From: LISTSERV List Owners' Forum [mailto:[log in to unmask]] On Behalf Of William Schults
Sent: Wednesday, April 19, 2017 7:41 AM
To: [log in to unmask]
Subject: SenderFilterConfig list
Can anyone help me interpret this message from the error log? I don't know what the SenderFilterConfig list is.
The subscriber's e-mail account is active, as she e-mailed me from her account to ask why she is not receiving posted messages from the list. My personal e-mails to the user are being delivered OK.
Last error: 5.7.105 554 5.7.105 SenderFilterAgent; Sender
denied as sender's email address is on
SenderFilterConfig list
Bill Schults
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