Delays in provisioning of user/mailbox or synchronizing changes in Exchange Online


When a user is created or changed in Microsoft 365, or synced to Microsoft Entra ID from the on-premises environment, either no mailbox is provisioned for the user, or the change isn't reflected in Exchange Online.



This feature requires a Microsoft 365 administrator account. This feature isn't available for Microsoft 365 Government, Microsoft 365 operated by 21Vianet, or Microsoft 365 Germany.

Select the button below to launch a diagnostic in the Microsoft 365 admin center. The diagnostic will guide you to resolve various error conditions that can cause mailboxes to not be created.

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.

If the diagnostic doesn't resolve the issue, use the following steps:

  1. Verify that the user is assigned a valid Exchange Online license in the Microsoft 365 admin center.
  2. Resolve any validation errors that the user receives.
  3. Check whether a Service Health notification in the Microsoft 365 admin center applies to your environment.

If the issue persists after 24 hours, contact Microsoft Support.