Microsoft has announced the end of support for Microsoft 365 Apps on older versions of Windows Server.
This is down to Microsoft's Modern Lifecycle Policy, which requires customers to stay current with the servicing and system requirements for their products and services.
Here's what you need to know about the end of support and the options available for customers.
From October 2025 Microsoft 365 Apps will no longer be supported on the following versions of Windows Server after the specified dates:
When Microsoft say "October", they mean that the security patches deployed during October 2025 patch Tuesday will be the marker for end-of-life. So, really, you until midnight Monday 13 October 2025 but don't leave it that late.
There's a critical point to note here.
Microsoft 365 Apps will still keep running after the 14 October 2025 and they will still keep getting security updates.
"Using Microsoft 365 Apps on older, unsupported operating systems may cause performance and reliability issues over time. These issues could include new features added to Microsoft 365 Apps, or updates to existing features, not working as expected."
The primary use case is Remote Desktop Services (RDS), aka Terminal Services. This is where end users connect onto a server for shared access. The server could be onsite in your server room or hosted in the cloud. That RDS Server will have Microsoft Office applications installed, Word, Excel and/or Outlook. It's these applications, collectively know as Microsoft 365 Apps, that will be unsupported.
Using Microsoft 365 Apps on unsupported versions of Windows Server can lead to performance and reliability issues.
New features and updates may not work as expected, potentially impacting productivity and security.
Therefore, organisations must plan their next steps to ensure continued support and optimal performance.
If you have compliance obligation to run supported versions and configurations, for example Cyber Essentials or ISO 27001, your compliance may be at risk as of October 2025 running Microsoft 365 Apps on Windows Server 2016 or Windows Server 2016 would be unsupported.
Moving to alternative solutions like Windows 365 or Azure Virtual Desktop can provide a more flexible and scalable environment.
These cloud-based solutions offer several benefits:
A complete software-as-a-service solution that streams your Windows experience from the Microsoft cloud to any device. It requires limited configuration and offers easy management through Microsoft Intune.
A highly flexible desktop and app virtualization service that runs on the cloud. It provides full control over management and deployment, with consumption-based pricing.
The end of support for Microsoft 365 Apps on older versions of Windows Server is a significant change that organizations need to address promptly.
By considering the options to retire, upgrade, or replace their current setups, organizations can ensure they remain compliant with Microsoft's policies and continue to benefit from the latest features and security updates.
Microsoft.com: Windows Server end of support and Microsoft 365 Apps
Microsoft.com: Microsoft 365 Apps migration from Windows Server
Microsoft.com: Windows Server 2019 lifecycle
Microsoft.com: Windows Server 2016 lifecycle
Microsoft.com: Windows 365
Microsoft.com: Azure Virtual Desktop
Microsoft.com: Office and Windows configuration support matrix
ctm-it.com: Windows 10 End-of-Life
ctm-it.com: Managed Services Infrastructure
If you need help migrating away from Microsoft 365 Apps running on legacy servers, please contact us now!