Configure Exchange 2013 Public Folders via Hybrid for Access with Exchange Online Mailboxes

There is nothing like trying to wade through the TechNet articles and decipher the instructions that are given. Don’t get me wrong, I love TechNet and all it provides but sometimes (most of the time) the documents lack clarity–but, maybe that’s by design.
 
Currently, I’m working on configuring Exchange 2013 public folders (on premise) to be accessible with Exchange Online mailboxes and am using this article … Configure Exchange 2013 public folders for a hybrid deployment.
 
I set it up in my lab environment and on premise PFs are accessible for an Exchange Online mailbox. Though it wasn’t immediate, I suppose the main ingredient after implementing might have been patience—because accessibility took well over 60 minutes to achieve.
 

This lab consists of:

• Windows 2012 R2 DC running AAD Connect v1.1.130.0
• Exchange 2013 CU12 configured for hybrid
• Office 365 tenant with E3 subscription

Basically, I followed the TechNet article and that was all.  However, I would like to provide some details that I feel are lacking clarity in the article.
 

• Prerequisites: All Office clients should be current with all the latest service packs and hotfixes.  NOTE: Only Office 2013 and newer for Windows and Office 2011 and newer for Mac are currently supported with Office 365. Older Office clients may work but are not supported with Office 365.

• Step 1: Nothing additional.

• Step 2:
  
  • Ensure that the PF mailbox AD object(s) and any mail-enabled PF AD objects (if any) are synchronized to O365 via AAD Connect
  • Run the following command from the Exchange Management Shell and is for the purpose of synching mail-enabled PFs permissions.
  • The command syntax must be formatted like this (quotes excluded) and run from the folder where the files in Step 1 were downloaded to…
    
    • “.\Sync-MailPublicFolders.ps1 -Credential (Get-Credential) -CsvSummaryFile:sync_summary.csv”
  • This command is strongly recommended to be run daily if there are mail-enabled PFs
  • Force synchronize with AAD Connect after running … via PowerShell on server with AAD Connect run (quotes excluded); Assumes AAD Connect 1.1.105.0 at minimum is installed…
    
    • “Start-ADSyncSyncCycle -PolicyType Delta”

• Step 3:
  
  • This step must be run from Azure AD Module for PowerShell to connect to O365 with PowerShell
  • The “RemotePublicFolderMailboxes” parameter in the referenced command refers to the name of the on premise PF mailbox(es)

One big takeaway that I feel must be understood is that these tasks do not migrate or synchronize public folder content from on premise to a public folder mailbox in Exchange Online. In fact, I don’t have a public folder mailbox in my O365 tenant. However, if all mailboxes are going to be moved to Exchange Online, you will eventually need to migrate the public folder data to Exchange Online to reduce latency accessing the on premise PFs and reduce bandwidth from O365 on your perimeter network.
 
And since Microsoft has no native method or elegant way of performing such a task I encourage a look at 3rd party solutions provided by BitTitan (my recommendation) or BinaryTree. Last year I tested BitTitan’s PF migration offering and documented it here.
 
Hope this helps.

Reference(s):

• Configure Exchange 2013 public folders for a hybrid deployment
• System requirements for Office
• Connect to Office 365 with PowerShell
• Exchange Public Folder Migrations with MigrationWiz