our Office 365 tenant domain has been blocked by Barracuda Email Security Service: I noticed this happened since several users got an NDR from different recipient domains protected by Barracuda.
The message they get it's always the same:
550 5.7.350 Remote server returned message detected as spam -> 550 permanent failure for one or more recipients
The only way we have to sort it out is to contact the recipient's email admin and ask them to add our domain name to their list of allowed senders.
But this is happening with a Barracuda cloud solution and from different recipient domains so I assume it's somethig that only Barracuda engineers can fix globally.
I've already tried http://www.barracudacentral.org/rbl/removal-request but my mailboxes are hosted on Office365, and Microsoft doesn't provide the IP address of the EOP server who has contacted Barracuda: I've tried also to check my domain reputation at http://www.barracudacentral.org/lookups/lookup-reputationand but it still says that it's not a poor domain.
I'm not a Barracuda customer: who should I contact to be unblocked?
Any help would be greatly appreciated
Edited by Paccagnella Massimo, 10 October 2019 - 05:41 PM.