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Upcoming changes to license re-assignment in Exchange Online

The_Exchange_Team's avatar
The_Exchange_Team
Platinum Contributor
Mar 21, 2022

In this post we want to highlight some upcoming changes around license re-assignment in Exchange Online to help admins get clarity on mailbox behavior and how license re-assignment works. The new behavior for re-licensed users will be effective from about end of March 2022, onwards.

Current re-assignment behavior

When an Exchange Online license for a user is revoked, the user object is converted to a mail user (MailUser). When a license is re-assigned to the user, one of two things happen, depending on the timing of re-assignment:

  1. Exchange Online license re-assigned within 30 days after revocation. This is a straightforward scenario; if a user is assigned a valid license within 30 days of license revocation, their mailbox and all its data are reactivated.
  2. Exchange Online license re-assigned more than 30 days after revocation. The behavior depends on the type of user:
  • For a hybrid user, the mail user is not converted to a cloud mailbox because it is assumed that the license was revoked because the user was off-boarded from Exchange Online.
  • For a cloud only user, the amount of time elapsed since revocation doesn’t matter; when the Exchange Online license is re-assigned, the user object is converted from MailUser to UserMailbox.

New behavior

If the Exchange Online license is re-assigned even after 30 days, every user will have a mailbox assigned to them. With this change we are no longer assuming that the user was off-boarded after 30 days. Since the user had a mailbox when the license was removed, their mailbox will be reactivated after a license has been reassigned.

Note:

  • If after license reassignment, conversion of the recipient to UserMailbox was not intended, follow this process.
  • If license re-assignment happens after more than 30 days, a mailbox will be assigned, but it won’t have any previous mailbox content. If the license is reassigned within 30 days of revocation, then mailbox content will be restored.

Exchange Online Team

Published Mar 21, 2022
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14 Comments

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  • BrianAdmin's avatar
    BrianAdmin
    Brass Contributor
    Mar 22, 2022

    Does it mean returning user gets a brand new mailbox if a license is applied 30 days later?  What happens to the old emails if termed mailboxes were part of the Retention Policy to keep contents for 2 years? Thanks.

  • Scott_Schering's avatar
    Scott_Schering
    Copper Contributor
    Mar 22, 2022

    What about restoring a license to mailboxes unlicensed past 30 days but are under litigation hold?

  • Nino_Bilic's avatar
    Nino_Bilic
    Icon for Microsoft rankMicrosoft
    Mar 21, 2022

    JoeITGuy Nothing remarkable will happen; the mailbox should be converted to shared first and then a license can be removed (note though that such mailbox will be limited to 50GB in size and if the mailbox was over that limit, email will NDR with 'mailbox is full'). If then at the later date, the mailbox needs to be assigned to the user again, assign the license to the shared mailbox, convert to user mailbox. This article goes a lot deeper into what to do if someone is leaving a company: Remove a former employee - Overview - Microsoft 365 admin | Microsoft Docs

  • JoeITGuy's avatar
    JoeITGuy
    Copper Contributor
    Mar 21, 2022

    "If license re-assignment happens after more than 30 days, a mailbox will be assigned, but it won’t have any previous mailbox content. If the license is reassigned within 30 days of revocation, then mailbox content will be restored."

     

    With regard to the above, so what happens if you delete a departed user's account, removing the Exchange license and converting their mailbox to a shared mailbox, but then after 30 days the individual is hired back and you need to relicense the mailbox? Does their old mailbox and new one co-exist, and assuming the answer is yes, what's the best way preferred way to move historical mail from an old shared mailbox to a new and active one?

     

    If the above scenario sounds far fetched, you should meet the folks I work for. I've had to reactivate users that left the company on numerous occasions already. So far it's always been within 30 days, but I'm sure it's just a matter of time before I have to do this for someone that returns to the company after 31+ days...