Overview

While reviewing your transaction logs you discover several error messages that indicate a Mailstream block has been assigned to your internal IP address by various domains. You would like to understand why this is happening and whether or not you need to modify your ListManager's Server IP settings or some other setting to resolve the issue and allow mail to flow to the blocked domain. 

Sun, 11 Jul 2021 17:16:15 Sending email to: ((EMAIL ADDRESS)) <-- DNS info
available for: YOUR_DOMAIN.COM --> MailStream 'default' (IP address 10.0.0.1)
is known to be blocked by server(s): xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx,
xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx,
xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx, xxx.xxx.xxx.xxx --> No
more mail servers left to try.

Note: The xxx.xxx.xxx.xxx segments in the example above would be the IP addresses of the servers who are blocking your IP address. 

Information

ListManager will report the internal IP address that is assigned to the network interface card for the server when displaying Mailstream blocks and other Mailstream related functions. This is normal expected behavior and does not indicate a problem with the configuration of your server's IP address.

Even though ListManager does not translate the internal IP addresses to the external Network Address Translated IP address, block detection is performed accurately since blocks are determined by reviewing SMTP transaction codes and not IP blocklists. When requesting block removal from a domain, it may be useful to include the external IP address in the name of the Mailstream.

For guidance on removing Mailstream blocks, consult the Related Articles below.

Related Articles

• ListManager - Blocked by Mimecast
• ListManager | Mailstream blocks
• Releasing a Mailstream Block