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SMTP Blacklist?



I have two locations using the same outlook email address for SMTP notifications. Both stopped working around the same time period.

When I looked at an SMTP blacklist for both places they both did have a single blacklist. I tried changing emails and a few other things and both just won't send any email. The only thing using SMTP at either site is my PRTG server. Any idea why this would be happening or has anyone seen this?

notifications prtg smtp

Created on Mar 10, 2023 11:10:51 PM

2 Replies



Hi there,

Not sure on which version your PRTG server is at the moment. There was an issue in the version before version So if you did not yet install this update yet, go ahead and see if the issue is resolved by that.

Kind regards,
Felix Saure, Technical Support Team

Created on Mar 15, 2023 11:04:26 AM by  Felix Saure [Paessler Support]



This looks like it may have been it. I have updated and it appears resolved. I also switched over to gmail with app passwords as that seems a bit more of a secure way to do things.

Created on Mar 15, 2023 12:53:02 PM

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.