Hi @Samir Shrestha
From what you’ve described, this behavior typically indicates that the Exchange Online organization provisioning process is still pending or stuck in the backend.
The error returned by Enable-OrganizationCustomization “Enabling customization is not allowed because the Organization is currently being upgraded” means that Exchange Online still considers the tenant to be in an upgrade/provisioning state. Under normal circumstances, this process completes automatically. However, if it has remained in this state for more than 5 days and actions like mailbox creation did not trigger hydration, it is unlikely that there is anything further you can do from within the tenant to resolve it.
Additionally, the Enable-OrganizationCustomization cmdlet normally only needs to be run once. If customization is already enabled, running it again would typically return a different message indicating no further action is required. In your case, the error instead shows that the organization is still in an upgrade state, which points to a backend provisioning issue rather than repeated execution of the command.
Please note that we’re not Microsoft support, this is a user-to-user support forum. Moderators here don’t have backend access to Microsoft systems, so we can only provide guidance based on public documentation and cannot escalate this to backend.
If you have an active Microsoft 365 subscription and hold the Global Admin role, you can submit a support request directly through the Microsoft 365 admin center. Otherwise, please contact your IT administrator to raise a support ticket on your behalf.
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