EXO: Shared Mailbox with Active AD account

Copper Contributor



We are migrating our Ex2010 mailboxes to Exchange Online.

Currently, we have shared mailboxes created with an Active AD login account (Generic login) for application integration purposes.


What will happen to these shared mailbox (with active AD) if we do not assign O365 license to them post migration?

Will application continue to be able to login?


Understand that: Shared mailbox do not require an license. It should not be used for login.

But we need to understand the impact to our applications and if anything need to be done before migration?


3 Replies

There's nothing in the code stopping you from logging in directly to a Shared mailbox, it has been actually discussed few times here. However it's against the license agreement, and you should use it at your own risk. Best assign a license to the mailbox and covert it to regular one.

Hi @Vasil Michev 



Question: you mentioned convert to "regular" one = Does that mean Microsoft recommended Shared mailbox to be created as UserMailbox type in EXO?


What about assign O365 to SharedMailbox type? 


Thank you

No, it simple means you can convert between the different mailbox types with no issues, as long as you keep true to the license agreement. You can assign a license to a shared mailbox as well, but if you do that, you can simply convert it to user mailbox as you are allocating the license anyway.