Forum Discussion
Solved
OnPrem SMTP sending to Office 365 Encrypted
I have Internal servers relaying on a "on premise SMTP server" this smtp server has an Office 365 Exchange Connector configured a: From: Your organization's email server To: Office 365 Identity: f...
It's generally assumed that when you configure TLS, you would use a certificate associated with specific domain, so that the service can verify the sender. If you use the IP option, you should still be able to toggle the TLS requirement via PowerShell:
Get-InboundConnector Hybrid-In | Set-InboundConnector -RequireTls $true
Set the connector to require TLS as detailed for example here: https://technet.microsoft.com/en-us/library/dn751021(v=exchg.150).aspx