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Direct delivery using built-in email server (default)



We are using Direct delivery using built-in email server (default). But we got black listed and when sending notification we get log event:

"Your access to this mail system has been rejected due to the sending MTA's poor reputation"

What should we do?


mx notification-delivery notifications

Created on Jul 25, 2016 12:48:06 PM

Last change on Jul 26, 2016 12:22:31 PM by  Luciano Lingnau [Paessler]

1 Reply



Hello Aleksandar,
thank you for your KB-Post.

The default built-in delivery via MX records may not always work, because PRTG isn't designated as a "trusted" e-mail sender, this may lead to issues especially when trying to mail accounts from 3rd party domains.

For best results we advise you to switch to this option instead:

  • Use SMTP relay server (recommended inside LANs/NATs)

PRTG will then ask for the Address, port, account and authentication settings to connect to an existing SMTP server to relay messages trough it, making PRTG's correspondence "trusted" as long as your domain/mail server is trusted. This is the "regular" way which most application and e-mail clients use to operate.

There are some set-up instructions for public providers here:

Best Regards,
Luciano Lingnau [Paessler Support]

Created on Jul 26, 2016 12:27:53 PM by  Luciano Lingnau [Paessler]

Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.