Hi, I'm using Exchange 2003 with a mix of Outlook 2007 and 2010. My users are unable to send emails to certain external addresses. They will get back the following NDR.
Text
1 2 3 4 5 6 7 8 9 10 | Your message did not reach some or all of the intended recipients.
Subject: Test
Sent: 04/22/2014 5:09 PM
The following recipient(s) could not be reached:
external user on 04/22/2014 5:09 PM
You do not have permission to send to this recipient. For assistance, contact your system administrator.
|
I've checked with mxtoolbox but my domain does not appear to be on any public blacklists and this problem affects everyone on my domain. When I called the external recipient they said they weren't trying to block any emails from us.
When I check the message tracking center it says
SMTP: Started outbound transfer of message
SMTP: Non-delivered report (NDR) generated
Any ideas on what is causing this and how to get around it?