Address List and calendar Hybrid Exchange

[testoffice36578 testoffice36578]

Hello everybody,

First of all, sorry for my english.

I am currently configuring exchange hybrid. I migrated a mailbox on exchange online everything works. I have synchronized some users only with azure ad connect. Problem, how to have a common address list between exchange online and on premise. For that, I have to sync all users on Office365. In addition, do I have to see users on-premise in the online directory for the Free Busy.

Thank you

[#2]

Yes, you need to sync any contacts and users and groups over for anyone on the office 365 side to be able to e-mail on prem users. If you notice if you try to send e-mail to any of the users on-prem you will get an error because there is no route back to on-prem in your azure directory for the user.

Also any e-mail distribution groups you have the contacts/users of those also need to be synced as they cannot be in the groups without existing in the directories.

My suggestion is make sure when you do sync users across, you do not activate their exchange online license until you migrate them, there is a nasty bug that will create a mailbox on office 365 even thou they have an on-prem mailbox. If you wait till after you migrate mailboxes you won't have this issue.

[#3]

First of all, thank you very much for your answer.

I still have some point of interogation.

The mails work well between exchange online and on premise. If I understood to have an address list including all users on premise and online we need to syncronized all users? Then, the calendar sharing and delegation of mailboxes works?

Thank you

[#4]

Guess it depends how your e-mail routing is working, the way mine was setup I couldn't e-mail anyone from 365 to on-prem unless that object was sync'ed to 365 (didn't have to be migrated just exist as mail user in 365).

If however voodoo you have setup you can e-mail groups and people on-prem from your o365 account that's synced and migrated then in that case you won't be forced to sync those users and contacts yet, but to get sharing and all that you will need them to be in both places for sure.