Forum Discussion
Did Microsoft start blocking non TLS emails?
I'm starting to get complaints about external emails being rejected with the error: Remote host said: 454 4.7.0 Connection is not TLS encrypted. Recipient organization requires TLS. This appears ...
Yes, that's my server (Microsoft) rejecting emails because they are not TLS-encrypted. That is the error message the sender is getting. We were receiving non-TLS emails util the 27th, then they stopped coming through.
Check on the senders server if the outbound connector enforces TLS. If this is the case TLS-encryption is active and should work. Otherwise you have to contact microsoft maybe there is an issue in MS-datacenter