Licensed user with no email inbox


Dear Forum,


Yesterday i was checking some users in our tenant that have a few licenses properties assigned to their name. Out all of the options the most important one would be(for us in this case) Microsoft 365 Business Basic, which in our case would grant us email capabilities. Some users have additional features assigned to them such as Power Bi, Microsoft Power Automate Free and Dynamics 365 Customer Voice Trail. But seeing that a few of these users don't use the additional features i have removed, Dynamics and power Automate and left Microsoft 365 Business basic and Power BI.


After doing so the users were unable to get emails, and checking within admin center i have noticed that these users did not have a mailbox assigned to their names any longer.


What i could have concluded from a few forum posts, the easiest solution was to remove all the licenses, wait 15 minutes and reactivate the license for the users again.


We have a hybrid environment where our AD is being synced using ADsync and our mailexchange is on-premise. we migrated 90% of all users to O365 and the designated users none of them are created on the on-premise exchange.


This worked but my question is why is this happening and what could be the reason this is happening?

And if i remove a user's mailbox how long before microsoft actually removes the mailbox from my tenant?

2 Replies
Removing Dynamics/Power automate licenses should not affect the mailbox in any way, if you are certain you did not accidentally disable the Exchange plan as well, best open a support case and report this. You can also check the Audit log to confirm what license changes were made, it should be capturing at least the Remove license entries.

To answer the other question, the mailbox is removed ~30 days after removing the license.
Yes i made sure that i did not remove the MS Basic was not removed up removing other features such as Dynamics/Power automate. unfortunately audits was not turned on so i could not check if i could have accidentally remove MS basic.