Making Public Folders On-Prem available for Office 365 User

New Contributor

Hello Community,


I hope I have addressed my question correctly here.

We have a public folder structure on-prem which started to expand years ago and we are now on the way to the cloud (try) an AAD connector has already been set up and a hybrid exchange environment

what works as far as it should.

But there is a problem with our public folders. (non mail-enabled(130 mail enabled))
we have 230k(non mail-enabled) of them and most of them are sub folders in a root folder.
So there is a root folder with about 200k subfolders.
After the migrate of Mailboxes, however, we have to offer the user the opportunity to access these folders, as the business model depends on it!!
According to the limits from the Microsoft documentation, it is not possible to sync the folders via the AAD connector.
Unfortunately, I don't know where else to go to solve this problem.
because this root folder has so bloated over the years
Who has ever been in the same situation, what can we do here?


Many Thanks



1 Reply

Hi @MartinLangof1285 ,


you will have to configure synchronization of mail-enabled public folders and access for your office 365 users to enable hybrid use for public folders: