External SMTP SPAM

Hi @Olivier Terlez ,

Thanks for posting in our Q&A forum.

Agree with Brice mentioned, you can create a mailflow rule to change the SCL level to allow spam messages in. Please refer to: https://video2.skills-academy.com/en-us/exchange/security-and-compliance/mail-flow-rules/use-rules-to-set-scl

Another way to whitelist your domain to bypass the spam filter, step by step guide please refer to the below links:

https://www.alitajran.com/whitelist-domain-in-office-365-to-bypass-spam-filtering/

Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

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