October 2026 is poised to be a pivotal month for IT administrators, as it marks the end of support for several significant Microsoft products. Following the retirement of Windows 10 in October 2025, system administrators may have anticipated a brief reprieve. However, the upcoming year brings a wave of product discontinuations that could lead to challenges for those unprepared.
The first major casualty is Office LTSC 2021, which encompasses a range of applications from Access 2021 to Word 2021. To maintain support, organizations will need to transition to LTSC 2024 or, more likely from Microsoft’s perspective, migrate to Microsoft 365. While M365 offers a modern suite of tools, it may not be the ideal choice for organizations that prefer to avoid cloud solutions. The on-premises version remains a static snapshot of its initial release, albeit with ongoing security updates.
In addition to Office LTSC 2021, Windows Server 2022 will exit mainstream support on October 13, 2026, although extended support will continue until 2031. On the same date, Windows 11 24H2 Home and Pro editions will also reach their end of life, while the enterprise and education versions of Windows 11 23H2 will enjoy a slightly longer grace period, concluding on November 10.
Among the lesser-known products, Publisher 2021 will bid farewell to a legacy that dates back to its introduction as a desktop publishing tool for Windows 3.0 in 1991. Its discontinuation will mark the end of an era, with no successor or alternative to take its place, leaving behind its unique proprietary file format.
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In addition to these prominent software products, several services are also set to be retired, potentially causing further complications for unprepared organizations. Entra ID Sign-In risk policies, previously known as Identity Protection, will be phased out on October 1, 2026. Microsoft encourages administrators to transition to Conditional Access to ensure their policies adequately address user and sign-in risks. Failure to complete this migration by the retirement date will result in the loss of risk protection.
A reader from Register expressed concern, noting, “Given how many organizations use O365, I can’t see how disabling sign-in protection might go wrong.” Looking ahead to October 2027, the landscape appears calmer, with only SQL Server 2017 scheduled for retirement. Nevertheless, with October 2026 already brimming with announced terminations, it would be wise for organizations to prepare well in advance to ensure a smooth transition.
