What has just lost support in the practice, what to do, and the next deadlines up to 2027
On 13 October 2026, Microsoft stopped releasing security updates for several products that are very common in practices: Office 2021, Windows 11 Home and Pro version 24H2, and the last Windows Server 2012 servers. Everything keeps working, but a vulnerability discovered tomorrow will no longer be fixed.
Office 2021: no more security fixes
This concerns Office 2021 and Office LTSC 2021, with all their applications: Word, Excel, Outlook, PowerPoint and the others. It is the most sensitive point in the practice: Outlook and Word open attachments from outside every day, and these remain the most common way in for attacks.
Two options:
- a Microsoft 365 subscription: the Office applications are updated continuously, with no new deadline to keep an eye on;
- Office 2024, bought once: it is supported by Microsoft until 9 October 2029.
Windows 11 24H2: move to a supported version
Windows 11 receives a new version every autumn, and each version has its own end date. For the Home and Pro editions, version 24H2 has no longer received updates since 13 October 2026.
To find out a computer's version: Settings, then System, then About; the "Version" line shows, for example, 24H2 or 25H2.
A computer on 24H2 must move to a supported version, offered in Windows Update:
- 25H2, supported until 12 October 2027;
- 26H2, available since 29 September 2026, supported until 10 October 2028.
The Enterprise and Education editions on 24H2 remain supported until 12 October 2027.
A computer connected to a device (radiology, scanner, camera) is not updated blindly: first check with the device's supplier that its software is compatible with the new version, and carry out the update outside consultation hours.
Windows Server 2012 and 2012 R2: the last year is over
Since 2023, these servers had only been supported through paid extended security updates. Their third and final year ended on 13 October 2026: there are no longer any updates at all for these systems. A practice server still running Windows Server 2012 must be replaced without delay, especially as it often hosts the database of the practice management software.
The next deadlines
| Date | What loses support |
|---|---|
| 10 November 2026 | Windows 11 Enterprise and Education, version 23H2 |
| 12 January 2027 | Windows Server 2016; Windows 10 Enterprise LTSC 2021 |
| 12 October 2027 | Windows 11 Home and Pro, version 25H2; Windows 11 Enterprise and Education, version 24H2; SQL Server 2017 |
Note: SQL Server 2016, a database used by many practice software packages, has already been out of support since 14 July 2026.
Our IT hardware for dental practices page keeps track of the end-of-support dates that concern practices. Not sure which versions are running in the practice? Write to us: we take an inventory and tell you what to do, computer by computer.
Sources
- Microsoft Learn, "Ending Support in 2026", updated on 19 August 2026: learn.microsoft.com/lifecycle/end-of-support/end-of-support-2026
- Microsoft Learn, "Ending Support in 2027": learn.microsoft.com/lifecycle/end-of-support/end-of-support-2027
- Microsoft Learn, "Windows 11 release information", updated on 13 October 2026: learn.microsoft.com/windows/release-health/windows11-release-information
- Microsoft Learn, Office 2024 lifecycle: learn.microsoft.com/lifecycle/products/office-2024