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 **************************************** e-mail: [log in to unmask]<mailto:[log in to unmask]> **************************************** ________________________________ To unsubscribe from the LSTOWN-L list, click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTOWN-L&A=1 ############################ To unsubscribe from the LSTOWN-L list: write to: mailto:[log in to unmask] or click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTOWN-L&A=1