We got a few of these email delivery failed messages today. Our clients send out email messages thru our IIS 7.5 website. We have SMTP running on the webserver. This has been working great for a couple of years.
One client today sent out a maybe 2 thousand email messages, higher then normal, all legitimate of course. This was the FIRST time we saw these delivery failure.
And we always bcc an email address to ourselves such as Bill@[Company].com.
Question: Can we eliminate the delivery failure by raising our threshold of allows emails somewhere? Do we do this at the "Reporting-MTA", which is our IIS box? Or is this error coming from @[Company].com ? GoDaddy hosts our email @[Company].com.
Reporting-MTA: dns;mail.[name of our website].com
Received-From-MTA: dns;[name of our IIS WEB server]
Arrival-Date: Thu, 5 Apr 2018 14:55:16 -0400
Diagnostic-Code: smtp;550 5.1.0 <71.nn.nn.nn> This IP has sent too many messages this hour. IB504 <http://x.co/rlbounce>