Mail enabled Public folder not receiving external mail after batch migration to O365

Question

Just moved all PF's to Exchange Online.  Get this error when sending to the public folder from external email:

Diagnostic information for administrators:

Generating server: xxxxxxxxxxx.com

invoices@xxxxxxxx.com

#550 5.2.0 RESOLVER.PF.Invalid; misconfigured public folder mailbox ##

From Exchange Online:

PS C:\WINDOWS\system32> Get-OrganizationConfig |fl PublicFoldersEnabled

PublicFoldersEnabled : Local

On premise Exchange powershell:

PublicFoldersLockedForMigration : True

PublicFolderMigrationComplete   : True

Also from the public folder in question Anonymous is set for CreateItems through the Contributor role:

FolderName           User                 AccessRights                                                               SharingPermissionFlags                                                   

----------           ----                 ------------                                                               ----------------------                                                   

Invoices             Default              {CreateItems}                                                                                                                                       

Invoices             Anonymous            {Contributor}                                                                                                                                       

Invoices             svc_MioHost          {Owner}                                                                                                                                             

Invoices             Project Folder Admin {Owner}                                                                                                                                             

Invoices             _CRG Accounting C... {PublishingEditor}        

Any thoughts on what could be preventing external mail delivery?

Answer 1

Hi Charles,

Please feel free to let me know if you have any further concern.

Regards,

Alan

Answer 2

Hi Charles,

Via your description, my understanding is that the internal users can send to your PFs (Public Folders), right? And, does the issue persist with all the external user or just some specific one? 

Also, from the error message "Invalid; misconfigured public folder mailbox ##", please re-confirm whether you have typed the PF mailbox address correctly (I recommend you manually type the address but not auto-complete) while you were trying sending to it. 

If the abobe mentioned information has no problem form your side, then the issue might be related to the domain of the PF mailbox has been set to "Authoritative". Directory Based Edge Blocking (DBEB) allows any SMTP address that has been added to the service, except for mail-enabled public folders. And the possible solution should be to change "Authoritative" to be "Internal Relay". For more information, you can refer to https://technet.microsoft.com/en-SG/library/dn600322%28v=exchg.150%29.aspx?f=255&MSPPError=-2147217396. 

If the issue persists, I'd like to collect the following informatiom so that we can move forward:

1. Is your organization pure cloud (Office 365) or a Hybrid environment?
2. The complete NDR (Non-Delivery Report) while sending from the external address to the PF. 

For protecting your privacy, you can provide the NDR in the Private Message (PM).

Regards,

Alan