While testing email routing - I’ve notice one problem. From my company’s email I’m not able to send the email to the routed email address. mx.clouldflare.net is not accepting the email. Getting error message:
“mx.cloudflare.net
Remote Server returned ‘521 550 Upstream error’”
But strange thing is - it works fine when send from different email address/server. Even more strange - this is MS Exchange online, from another MS hosted email (but M365) it works fine.
Could you please share the domain you are using?
We are seeing a few email delivery rejection from the upstream:
5.7.1 Our system has detected that this message is likely unsolicited mail. To reduce the amount of spam sent to [...], this message has been blockedALL emails sent from atec-it.at are getting rejected. All the others end up in spam on GMail.
I have tried to send a real email I received on my work email, not just some “test” emails.
Hi @sven2 - any news? were you able to find anything ?