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Unable to create the hierarchy serving public folder mailbox, receiving a error message - exceeded the resource quota (100) enforced by policy "Recipient Quota Policy: PublicFolderHierarchyMailboxCountQuota" Please note there an no Public Folder Mailboxes showing in our tenancy.
I am however able to create secondary non-hierarchy serving public folder mailboxes using powershell.
Any help would be appreciated.
Is it the pure Exchange Online? Did you have migrated PF from Exchange On-premises?
You mentioned that you cannot create hierarchy public folder mailbox, but you can create secondary non-hierarchy serving public folder mailboxes, how did you verify this? Because the only difference between creating the primary hierarchy mailbox and a secondary hierarchy mailbox is that the primary mailbox is the first one created in the organization. How did you create the primary mailbox?
Please run the following command to verify that you have successfully created the primary public folder mailbox:
Get-OrganizationConfig | Format-List RootPublicFolderMailbox
Reference: Create a public folder mailbox in Exchange Online | Microsoft Learn
Hi thanks for your reply. No migration has yet been attempted. There is no primary public folder mailbox.
Again I am unable to create a public folder mailbox in either in the GUI or powershell.
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I can confirm that I am seeing the same issue in multiple M365 tenants. No pre-existing PF mailboxes in EXO, but unable to have any PF mailbox serve as a hierarchy.
Thanks for the information, and based on my research, there is an related SI : EX747087 Users were unable to create public folder mailboxes in Exchange Online, I suggest you contact M365 backend team for help via Service Request in M365 portal.
Hi Jayce, you can create PF mailboxes if you set IsExcludedFromServingHierarchy to $True. However, you need this set to $False for the hierarchy to propagate to other PF mailboxes. Considering in my case we only have a few, and not 100 in this state, I shouldn't be seeing this error.
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Can confirm that this is a wider issue possibly impacting all Exchange Online tenants. Attempted a PF migration and ran into the exact same error creating the initial public folder mailboxes in Exchange Online. I've opened a service ticket in order to escalate to the exchange backend team. Several days and phone calls later the ticket remains in an unassigned state despite the 8 hour SLA.
After many days waiting, Microsoft Backend Support finally remediated our tenancy. All good now.
I so glad to know this issue is resolved, yes, since all the configuration are correct, it should be backend issue which must connect to backend team. Thanks for your understanding, hope to work with you again.