I have just received the message below from JRiver (I have deleted parts of my email address to avoid the attentions of any malicious web crawlers).
My first reaction was that it looked suspiciously like spam but other posts to this forum about similar messages suggest that it is actually a valid automated communication from JRiver. It claims to provide the text of a bounce message received by the JRiver server when trying to email me but doesn't actually tell me anything beyond saying that it is a "failure notice".
On checking my inbox, I now see that the last communication I received from JRiver was on 20 March 2014, which explains why I never received any advance notification of the MC20 upgrade. I haven't changed my email address for many years and am unaware of any problems with my email account (I get loads of emails every day).
I have sent a blank message to mlist-subscribe at listserver.JRiver.com as requested, which I trust will fix this problem. However, it is not clear why any such action was necessary, given that the warning message below was sent to my correct address!
David
EDIT: After sending that blank message to the JRiver server I received an email stating that I "was already on the mlist mailing list". It looks like JRiver's mailing list process needs a little remedial care and attention...
=========================================================
Hi! This is the ezmlm program. I'm managing the mlist at listserver.JRiver.com mailing list.
Messages to you from the mlist mailing list seem to have been bouncing. I sent you a warning message, but it bounced.
I've attached a copy of the bounce message.
This is a probe to check whether your address is reachable. If this probe bounces, I will remove your address from the mlist at listserver.JRiver.com mailing list, without further notice. You can re-subscribe by sending an empty message to the following address:
mlist-subscribe at listserver.JRiver.com
--- Enclosed is a copy of the bounce message I received.
Return-Path: <>
Received: (qmail 19899 invoked for bounce); 19 Aug 2014 11:50:38 -0000
Date: 19 Aug 2014 11:50:38 -0000
From MAILER-DAEMON at webserver.JRiver.com
To: mlist-return-warn-1408448881.fdolblmaefelepkneohi-david.XXXXXXX=XXX.co.uk at listserver.JRiver.com
Subject: failure notice