Problem Statement  

If you are a company currently using an on-premises Microsoft Exchange Server environment, then you have a crucial decision to make based on upcoming dates in the Microsoft support lifecycle.  

The important thing to note here is the extended support end date for Exchange Server 2016 and Exchange Server 2019, which for both products is 14^th Oct 2025. It is not often that two major releases of a Microsoft product have the same end date for extended support, but that is the situation.  

The next important date you need to consider is the release date of the next version of Exchange Server, which we will call Exchange Server vNext. Currently, the release date for Exchange Server vNext is the second half of 2025. This information is available on the Exchange Team Blog.  

But wait, isn’t the end of extended support for Exchange Server 2016 and Exchange Server 2019 also the second half of 2025?  

Yes, it is! And therein lies the problem: Whether to upgrade to Exchange Server 2019 or stick with Exchange Server 2016?  If you are running Exchange Server 2013, to keep any support you should have already planned and executed a move to a later version of Exchange Server, which may as well be Exchange Server 2019.  

Supplementary Details  

The vital information you need to know is how you move from Exchange Server 2016 or Exchange Server 2019 to Exchange Server vNext.  

• To move from Exchange Server 2016 to Exchange Server vNext, you must perform mailbox moves from your current environment to your new environment because you cannot do an in-place upgrade.  
• To move from Exchange Server 2019 to Exchange Server vNext, you will have the choice of much simpler in-place upgrade.  

For businesses with anything other than a very simple deployment of Exchange Server this causes a few problems. These problems are multiplied if you have a larger deployment of Exchange Server, or you are using Database Availability Groups (DAGs). You have some significant planning to do if your organization is in one of the above-mentioned situations.  

Recommendation

We have a large corporate customer with forty-eight Exchange Server 2016 servers spread across a main site and a remote Disaster Recovery (DR) site configured with three DAGs hosting 40k mailboxes. For them planning a move that involves 40k mailbox moves across to new Exchange Servers will take approximately 12 months, but they only have four at most if Exchange Server vNext is released on the 1^st of July. Their best plan is to first move from Exchange Server 2016 to Exchange Server 2019 so that when Exchange Server vNext is released they are left with a simpler in-place upgrade.  

From a corporate risk perspective being on an unsupported platform is unacceptable, so this risk needs to be minimised as much as possible. The best way to minimise that corporate risk is to start planning a move to Exchange Server 2019 as soon as possible so you put yourself in the best possible position to move to Exchange Server vNext as quickly as possible.  This is also Microsoft’s recommendation.  

How Can Oivan Help?  

Our team of Microsoft architects and consultants can help you understand the challenge and help you understand how you should proceed. Especially with larger businesses, Oivan can help you understand how to move your current Exchange Server architecture and design to Exchange Server 2019, so you are in the best position possible to move to Exchange Server vNext when it is released in 2025.  

Oivan has experience performing Active Directory health checks so that your Exchange Server environment is stable when you move to Exchange Server vNext. Oivan can also help you improve the security of your Active Directory environments to mitigate any credential threats that could expose your Active Directory’s privileged accounts.  

Oivan can also help you with any plans you have around Microsoft 365 and Azure. We have certified and experienced professionals who can help you plan your organisation’s plans to modernise how you work by guiding you when implementing Microsoft’s cloud services. Whether that is migrating to Microsoft 365 to give your users a more flexible and dynamic working environment, extending your Active Directory and other servers to Azure to improve your DR options, or thinking about deploying a SIEM (Security Incident and Event Management) solution in the cloud, Oivan is here to help.