Migrating Shared Mailbox to O365 Group?

Copper Contributor

I need to delete an inactive mailbox - A 6 months retention policy is in place, the user was removed from AADConnect synced OU, the license was removed from his O365 account thus his mailbox is in inactive state. Subsequently the user has been moved into a Synced OU, it's exchange attributes cleaned and the inactive mailbox restored (i.e. copied into the new user mailbox).

As per current regulations I now need to delete that inactive mailbox.

Documentation seems outdated:


I already had a look at this:


Do I have to wait for the Retention Policy to expire or is there a way to remove the mailbox?



3 Replies
Hi Michelangelo,

You don’t have to wait. Remove the inactive mailbox from the hold policy and Office 365 will delete it.


Best, Chris

Unless there's another hold in place that affects the mailbox...

Remember too that the mailbox must be processed by the Mailbox Folder Assistant before it will be removed. The assistant makes sure that no holds are in place that would keep the mailbox, and if none are found, it removes the mailbox. It can take up to seven days after removing the final hold before an inactive mailbox is finally removed.