Many companies are still using the on-premise version of Exchange Server. And the IT departments have faced the decision of migrating currently used variant. You ask yourself the question: is a migration to Exchange 2019 worthwhile? And if so, how much effort does a migration mean? Some days ago Microsoft has released the 2019 version of the Exchange server, here the most important information we need to know about it, to be able making a decision, if we want to migrate or not. Here are the most important news we need to know about Microsoft Exchange server 2019:


Operating system

At the Microsoft Ignite 2018 in Orlando Exchange server 2019 were presented to the crowd. The same about new Windows Server 2019. Microsoft Exchange 2019 will be supported only by running on Windows server 2019. Microsoft even says that the new Exchange should be installed on the core edition of Windows server 2019. However, the AD FFL has to be at least 2012 r2 or higher. Microsoft says that the new security features of the Windows server 2019 are that high, that this is the only right decision they could make. By the question why to use the core edition was the answer also clear: as less not needed tools are installed on the server as smaller is the footprint we leave behind us on the server. No one needs an installed JAVA or FLASH player on an Exchange server. Managing the Exchange server by itself should anyway be done by a tool-server remotely. Another reason for that is to safe performance. No GUI means also less patching and less burned performance.


Other system requirements

Aside from the Operating System requirements there are also some other we need to know. As written earlier Exchange 2019 also needs at least the Active Directory function level of 2012 R2. Another point is the .NET Framework, this has to be at least installed in the version 4.7.3. Microsoft Exchange 2019 also supports new Solid State Drive Hardware (MCDB) and large Memory (up to 256GB). Last but not least, Exchange 2019 increased the core density (Dual Socket).


Developing (On-premises vs online)

Until the Exchange version 2016, Microsoft has built on-premises Exchange servers and Exchange online (Office 365) together, at the Ignite this year in Orlando, they showed us the following slide about that:

As we can see on this slide, the development was linear for Exchange online and on-premises.


From now with Exchange Server 2019 there are two independent streams:

As we can see, Exchange online will be developed with new features and bug fixes independent of the on-premises versions in Exchange. However, that means that shortly or lately there will be differences between on-premises and online Exchanges.


TLS support

Since November 1st Microsoft has changed the TLS to 1.2 for all environments. Exchange 2019 has even no opportunity to change back to the old standard. That means Exchange 2019 supports TLS 1.2 only.


Outlook Anywhere

On Exchange 2019 RPC/HTTP is not supported anymore.


EAI support

The new Microsoft Exchange server is now more “internationalized”, that means EAI E-Mail addresses are now supported. That means we can use now Cyrillic, Greek, Japanese, etc. letters to send E-mails to our destination or to receive them.


Unified Messaging

One of the biggest changes in Exchange 2019 is that there is no more Unified Messaging on it. This role has to be replaced with a cloud voice mail, audio files will be delivered as E-Mail attachments. Cloud voice mail or a 3rd party PBX can deposit voice mails into Exchange via EWS or SMTP where they will be stored as attachments. If we migrate from a previous Exchange Version like 2013 or 2016, UM enabled mailboxes will be automatically UM disabled by migrating to Exchange 2019.



As I already mention that in the operating system chapter, Exchange 2019 supports now Windows Server core. This reduces the possible attack surfaces at the OS level. However, new is also that we are now able to restrict EAC/RPS access from the intranet.

Another thing in this topic is that Exchange 2019 enhanced auditing events. This point can help us to control suspicious popups form the point of an admin view.



Microsoft Exchange 2019 comes with a brand new search engine! The Exchange Team has worked together with the Microsoft Bing team to increase the quality of message searches for the end-user.

If we are running Exchange 2013 or Exchange 2016 we have experienced issues with indexing and health status of Database copies being ‘unhealthy’. This can become an issue when we want to failover to another Exchange server.

In Exchange 2019 this will improve with the introduction of a new search engine called ‘Big Funnel’. Indexing will no longer be in separate files, but it will be included in the Mailbox database. And since Mailbox database copies are always in sync (or at least they should be) this should result faster failover times, less complexity and less issues.


New developments in performance as well, since Microsoft is supporting SSD disks for Mailbox databases. But it’s a bit more granular than this. Only parts of the Mailbox database need to be stored on the SSD disks. For regular Mailbox items it doesn’t make sense to store them on SSD, and regular JBOD storage will do, but the ‘metache’ information, stuff that gets accessed frequently and randomly can be stored on SSD disks.


New User Experiences

Some improvements in the User Experience area. Calendaring has always been an issue. In Exchange 2019 we will see improvements like ‘do not forward’, simplified sharing and better OOF (Out-of-Office) handling. There will also be a Remove-CalendarEvent cmdlet in PowerShell, which allows administrator to remove calendar events.

Here is an example, how this could look like:

Remove-CalendarEvents -Identity “Greg Taylor" -CancelOrganizedMeetings -QueryStartDate 11-1-2018 -QueryWindowInDays 120

However, there are more PowerShell improvements, it will be possible to assign delegate permissions using PowerShell!



Exchange 2019 is more secure than the previous versions. From my point of view it is cool, that OS core is supported. This really helps by patching the whole Exchange farm in the future. Another point is that UM is not a part of Exchange 2019 anymore. From my point of view it is the right step. However, some customers are still sceptical about this decision. If you don’t want to implement a new 3rd party solution as an alternative to the UM of Exchange, you still can run Exchange 2016. The support of Exchange 2016 still runs until October 2025. This gives you enough time for the new implementation.



Photo by Lora Ohanessian on Unsplash