I have a fully functional Hybrid setup between my on-premise Exchange 2013 and my Office 365 exchange Online tenant. I can migrate mailboxes without issue.
Single Inbox works for my on-premise mailboxes. If I take a mailbox that is on-premise, which has SIB functionality working, as soon as I migrate it, SIB no longer works. We do not use Viewmail, and we are not using Text to Speech.
I have followed the guidance here: Configuring Cisco Unity Connection 9.x and Microsoft Office 365 for Unified Messaging
and here: Cisco Unity Connection with Office 365 (Hybrid)
and here: O365 Integration with Unity Connection
I have tried contoso.onmicrosoft.com, contoso.mail.onmicrosoft.c
om, and I have tried Outlook.office365.com, as per the recommendations in the referenced URLs above.
If I choose the search option, as the Cisco documentation recommends, all of them fail.
If I choose to specify the server, the only one that works is outlook.office365.com.
When I go to test an actual user that has been migrated, and was working prior to being migrated, and the messaging service has been updated on the user's inbox in Unity for O365, it fails, as though it is an invalid username or password. (401, I believe).
I am pulling my hair out - Unity Connection is the only thing standing in my way of finally migrating 1,000 mailboxes to O365.
Any advice would be very much appreciated.