The latest downloadable build of Exchange Server 2016 Cumulative Update 9 disclosed information that was previously shown accidentally to the public by Greg T. during his breakout session BRK3249 – Modern Authentication for Exchange Server On-Premises at Microsoft Ignite 2017.

As part of the global harmonization of the product namespace of the well-established Outlook brand, the next release of Exchange Server will be named Outlook Server 2019.
This name change was mentioned originally on this slide:

Give it a thought, and you’ll realize that this change makes absolute sense, as different product names for the same software function distract customers and users.
- Outlook
- Outlook for iOS
- Outlook for Android
- Outlook on the web
- Outlook Server
Another reason for renaming Exchange Server is a new functionality for integrating personal mailbox files (PST). It was and still is a tedious task for administrators to get hold of all those PST files used by end users. Instead of implementing a complex and data protection safe process to import PST files to the primary users’ mailbox, the new Outlook Server 2019 offers synchronized PST folders. A functionality we’ve waited for for years.
Two new functions are introduced as part of the new modern Outlook Server 2019
- PST Sync
Synchronized PST files across DAG member servers - Linked PST Files
New Outlook function to connect to server-based PST files advertised by AutoDiscover
How does it work?
- The $env:ExchangeInstallPath contains a new folder named PSTSync
The new folder can be accessed by end users using https:///PSTSync - Add a new subfolder for each user with PST files, assign Owner access to the subfolder, and inform the users to upload their PST files using that link
- The uploaded PST files are automatically renamed and synchronized between the DAG member servers using PSTSync
- Existing PST files are automatically advertised by AutoDiscover as LinkedPSTFile when queried by a modern Outlook version
The following diagram illustrates the new functionality in a simple Outlook Server 2019 setup:

The following screenshot illustrates the new PSTSync folder and some sample PST files for a user with SAMAccountName JohnDoe

It’s good the see that there is a future for an email server product like Exchange Server and that after so many years of cloud-only an on-premises-only feature got added.
Links
- BRK3249 – Modern Authentication for Exchange Server On-Premises
- More on Exchange Server 2016 CU9
- Official Link: https://goo.gl/QiTtDo
Enjoy the day, and Happy Easter!