Hi,
I am attempting to get outbound address rewriting working for mailboxes in Office 365. Given that this functionality doesn't exist in O365, I have enabled centralized mailflow so all incoming and outgoing mail is directed through the on-premise Exchange servers (Mail/CAS) and Edge server, configured in hybrid mode. Mail is flowing properly, and routing through the edge server as it should.
I have ensured that the outbound address rewrite agent is enabled:
[PS] C:\Windows\system32>Get-TransportAgent "Address Rewriting Outbound Agent"
Identity
Enabled Priority
--------
------- --------
Address Rewriting Outbound Agent True 1
And I have tested outbound rewriting. It works for mail sent from on-premise mailboxes, however it does not work for mail send from an Office 365 mailbox.
So I know that the address rewrite agent works and is configured correctly, but I don't know why mail routed through the edge server does not get filtered by the transport agents on that edge when coming from Office 365. Is this something to do with the send/receive connectors related to the hybrid configuration? Do I need to disable TLS or something like that? The most important question is: can this even be done?