I have a problem with a FortiMail VM. I use my Fortimail as a gateway. Unfortunately, I have a loop when sending emails, which I cannot solve.
The following error scenario:
When I send an email from my M365 mailbox to another M365 mailbox this email goes into a loop and rejected with this error: "Remote server returned '554 5.4.6 < #5.4.6 SMTP; 554 5.4.6 Too many hops>'". When sending from my M365 to email addresses outside the Microsoft Cloud, the sending is successful.
Can you help me to solve this problem? I suspect the problem is because the 365 accounts are all accessible via the same IPv4 address?
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