Outage with Exchange Online?

Question

Greetings, We have a user who was created and licensed about 4 hours ago but their Exchange Online mailbox still is not provisioned. The message in M365 Admin for the user when you click on the mail tab is We are preparing a mailbox for the user.

User was able to access other 365 services. User is Hybrid synced.

Answer 1

The service typically takes less than 30 minutes to provision a user or to sync changes for a user. However, in some situations these processes can take up to 24 hours, especially in hybrid environments. You can verify that the user is assigned a valid Exchange Online license in the Microsoft 365 admin center.

Answer 2

Hello, @mpls,

Welcome to the Microsoft Q&A platform!

You mention the user has been assigned a valid Exchange Online license, it is recommended for you to run the following PowerShell command to check the user's authentication status:

Get-MsolUser -UserPrincipalName <UserPrincipalName> | fl ValidationStatus,UsageLocation,*error*

If the ValidationStatus is not healthy, there might be sync errors in the synchronization process.

After checking that the user's authentication status is correct, as Amit Singh mentioned, mailbox configuration can take up to 24 hours, especially in mixed environments. During this time you can also use the diagnostic tools in the Microsoft 365 Admin Center to identify and resolve issues related to mailbox configuration according to Delays in provisioning a user or mailbox - Exchange | Microsoft Learn.

Should you need more help on this, you can feel free to post back. 

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Thank you for your support and understanding.

Best Wishes,

Alex Zhang