troubleshooting Question

Email Delivery Issues -- 554 Denied

Avatar of ncomper
ncomper asked on
Email SoftwareExchangeAntiSpam
5 Comments3 Solutions1263 ViewsLast Modified:
Morning all,
     I have an issue with Email delivery. My Client has purchased a new Domain and we have added this into the Exchange. Mail flow from the network is as follows:

Users > Exchange > Mimecast > External addresses
External Addresses > Mimecast > Exchange > Users

On sending test emails out from the Client account I have tested to Hotmail, Business address (365) and Gmail and mail flow both directions seems to work. Only when they are setting up from other external addresses do we see issues. Initially I thought this was bad external email addresses from poor data but the users still report issues and the bounce backs are as follows

This is a delivery failure notification message indicating that
an email you addressed to email address :
-- XXX@ExternalCo.com

could not be delivered. The problem appears to be :
-- Recipient email server rejected the message

Additional information follows :
-- 554 Denied [XXXX.XXXX.net] (Mode: normal)

This condition occurred after 1 attempt(s) to deliver over
a period of 0 hour(s).


If you have any tests I can complete please let me know  (I have done the basics) but pretend that I haven't just in case I missed anything

Thanks
ASKER CERTIFIED SOLUTION
ncomper

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