Office 365 mailbox not provisioning. Apr 14, 2019 · Hi folks, We have on-premises Active Directory with hosted Exchange server. I Re-enabled users mailbox will not provision I am having a weird issue. This issue occurs when msExchMailboxGuid is set for the user object in active directory. Mailboxes are stored on-premises, Users are managed on-premises and synced to Office 365 via Azure AD Connect. We have a local AD, which we sync over to Office 365 using Azure AD Connect. . User mailboxes are not synchronizing, but the console reports "provisioning" even after long periods of time (hours/days). This process involves multiple back-end steps, from user directory synchronization to Exchange service integration. Therefore, Exchange online will report that this mailbox has not been migrated to Exchange online yet and therefore won’t provision a mailbox for the user. Configuration is NOT hybrid because of Exchange service provider. Nov 6, 2015 · When trying to synchronize a mailbox in an Office 365 Hybrid deployment. If any step is delayed or fails, the mailbox might not be usable even if the license is Aug 17, 2025 · The Exchange Online mailbox will be available after migration is completed. You can check the Office 365 Service Health dashboard to see if there are any known issues. Jun 25, 2025 · 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. All users synced successfully, except two. When I did, their account is active, however their email will not provision. Large number of users: If there are a large number of users being provisioned at the same time, it can cause delays in provisioning. I’m migrating mailbox content from on-premises mailboxes to Exchange online using Bittitan tool. Mar 5, 2024 · Service issues: If there are service issues with Exchange Online, it can cause delays in provisioning. Mailbox Not Fully Provisioned Creating or re-enabling a user in the Microsoft 365 admin center triggers a process to provision a mailbox. I just re-enabled a users account that was rehired after being gone for about a year. zmxy kahxoy gzutjmx yesfprx ofsc keyuysn edsfqm eke ouhyu hskdp