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Microsoft introduced the subscription license back in 2011 with the release of Office 365, and now, in 2025, the same licensing mechanism will be applicable to the On-Premises Exchange Server. With the newly launched Exchange Server Subscription Edition (SE), Microsoft is moving away from the traditional perpetual license model.
According to many reports, the growing need for fast security and feature updates in an increasingly threat-heavy environment is one of the major reasons for this development in the license model. With this move, the Exchange Server now falls into the Microsoft Modern Lifecycle Policy that makes sure organizations receive ongoing security patches and feature rollouts as quickly as possible.
Now that Microsoft has officially ended support for Exchange Server 2019 and 2016 On-Premises versions, the need to shift to the SE version is more than ever. Moving further in this blog, we will learn how to safely update from your current Exchange Server to the Exchange Server Subscription Edition Version.
Changes in New Exchange Server Version and License?
If this is your first time updating the Exchange Server, you must be wondering what a license is in Exchange Server. To put it simply, it’s just a digital key or valid proof that grants you the right to keep using all the services of your Exchange Server and get regular updates.
Now, the next question is what you get in the new Subscription Edition. While the internal architecture of the Subscription Edition (SE) is nearly identical to Exchange Server 2019 CU15, the biggest change is the all-new subscription-based license model. The new model gives you the combined benefit of a valid license and the Software Assurance.
From an Exchange Server admin point of view, the new SE version should decrease administrative complexity over time. Administrators no longer need to plan and execute a massive, multi-server upgrade project every five years. The underlying deployment and configuration will mostly be the same.
Some users may find the subscription-based model slightly more costly than the old license model. But considering the security factors and on-time updates, upgrading to the new model is crucial to avoid costly security breaches and downtime.
Things to Consider Before You Upgrade
To guarantee a 100% successful upgrade, you must take care of the following prerequisites:
- Verify the Server version and figure out what upgrade path you must take. Depending on your current Exchange Server version, you can either have an in-place upgrade or a legacy migration.
- Check and install any server-specific hardware requirements to avoid any performance issues during and after upgrading to the Exchange Server Subscription Edition Version.
- Buy a valid Subscription Edition license and back up the complete Exchange Server data with an EDB to PST Converter tool.
- Analyze and filter data to avoid storage wastage and pick suitable non-office hours to minimize the server downtime as much as possible.
- Put the server into maintenance mode to isolate it from the production environment. Whether you update a Server or migrate EDB to Live Exchange, the maintenance mode is essential to avoid data corruption.
Step by Step Process to Update the Server
As we learn above, you can update the Server in two ways. Let’s see the process overview for both.
In-Place Upgrade
This method of upgrading the Server is the easiest one. However, you can only use this method if you have Exchange Server 2019 CU14 or CU15 installed. Here’s how to do it:
- Run the Exchange Server SE setup program directly on the Exchange 2019 server.
- The setup process will automatically detect the existing Exchange 2019 installation.
- Follow the on-screen prompts to proceed with the upgrade. The process will function like a major CU installation, updating the code base and the version designation.
Legacy Migration
This method is necessary when you are migrating from older versions, like Exchange Server 2016. It is more complex and time-consuming than the in-place method.
- Deploy a new Server with a supported environment and install all required roles and features.
- Install a fresh copy of Exchange Server Subscription Edition along with any latest cumulative update.
- Configure the new Exchange SE server to handle client access, internal/external mail flow, certificates, etc., services.
- Migrate all user mailboxes using the Exchange Admin Center (EAC) or PowerShell cmdlets (New-MoveRequest or New-MigrationBatch).
- Remove/uninstall the old Exchange Server 2016 to free up resources.
However, if you can afford it, we recommend that you first migrate Exchange 2016 to Exchange 2019 CU 15 version and then perform an in-place upgrade to SE versions. This approach is considered low risk. You can use the steps above to move mailboxes from 2016 to 2019 or rely on a professional Exchange migration tool for quick and error-free migration.
Note: If you directly want to migrate or upgrade your existing Exchange Server version to Microsoft Exchange Server Subscription Edition version, contact our support team.
What to do if Something Goes Wrong?
In-place upgrade or the legacy migration, both involve technically complex steps. Any inexact action may lead to data corruption or permanent loss. To prevent losing crucial user mailbox data, the Exchange admins always have an Exchange recovery tool as backup. A capable recovery tool can help you repair EDB files and recover lost/corrupt data while maintaining the original file attributes and folder structure.
A tool that I highly recommend and have used a couple of times myself to fix my Exchange database files is Kernel for Exchange Server. This is a one-stop solution to handle any type of Exchange issues. Whether it’s corruption, data loss, email backup, mailbox migration, etc., the tool can do it all, 100% error-free.
Conclusion
The method to upgrade to the new Exchange Server Subscription Edition version depends on your current Exchange Server. For Exchange Server 2019 CU14 or CU15, the process is simple. However, for organizations with older versions, like 2016, the upgrade may get complex. Use the information we discussed in this blog to safely move to the new Exchange Server version. However, in case you suffer any kind of data loss or damage, immediately use the professional Exchange data recovery tool to avoid permanent data loss.
Frequently Asked Questions
Ans. If you want to get latest security updates and keep using the on-premises/hybrid Exchange Server environments, you must update to the SE version.
Ans. Windows Server 2022 is the recommended OS for installing the Exchange SE version. This OS currently has the longest support lifecycle.
Your first line of defense is your full server backup. If a clean restore fails, a specialized EDB repair tool like Kernel for Exchange Server can be used to recover inaccessible mailboxes.
