How do I upgrade from Office 2021 before support ends this year?

Is it safe to keep using Windows 11 24H2 after October 2026?

We have entered a significant transition period for the Microsoft ecosystem. As 2026 progresses, IT administrators and individual users must prepare for the retirement of several critical platforms. Continued use of these products after their respective cutoff dates poses security risks due to the cessation of vulnerability patches.

Below is the strategic breakdown of products reaching their end of life (EOL) this year and the necessary upgrade paths to maintain system integrity.

Windows 11 Version 24H2: Prepare for October EOL

Deadline: October 4, 2026

Windows 11 version 24H2, released in late 2024, approaches its mandatory retirement. After October 4, Microsoft will stop distributing security updates for this version. Devices remaining on 24H2 will become vulnerable to new exploits.

The Upgrade Path: Version 25H2

Migration to Windows 11 version 25H2 is the required solution. This update functions as an “enablement package.” It activates features already present but dormant in the 24H2 operating system files. Consequently, the update process is rapid and carries a low risk of software incompatibility.

Early testing indicates high stability. Users should initiate this upgrade immediately rather than waiting for the October deadline. Microsoft typically begins forced upgrades on consumer devices as the EOL date draws near to ensure network safety.

Windows 11 SE: Final Updates for Education Devices

Deadline: October 2026

Windows 11 SE, the cloud-first operating system designed for K-8 education markets, will receive its final patch this October. This specific iteration of Windows 11 24H2 was intended to compete with ChromeOS but saw limited adoption. Schools utilizing these devices must plan for hardware replacement or an operating system migration if the hardware supports standard Windows editions.

Windows 11 23H2: Enterprise and Education Editions

Deadline: November 10, 2026

While consumer support for Windows 11 23H2 ended in late 2025, commercial editions retained an extended lifecycle. This grace period concludes this year.

Organizations running Enterprise, Education, or IoT Enterprise editions of version 23H2 must upgrade their fleets before November 10. Failure to update leaves corporate networks exposed to security flaws discovered after this date.

Office 2021 and LTSC: Planning Your Migration

Deadline: October 13, 2026

Office 2021 follows the “Fixed Lifecycle Policy,” providing five years of support from its initial release. This support terminates completely on October 13, 2026. This deadline applies to:

• Office 2021 (Consumer)
• Office LTSC 2021
• Office LTSC 2021 for Mac

Action Required

Software updates will not convert Office 2021 into a newer version. These are distinct products requiring a new license. You have two primary options:

1. Purchase Office 2024: This is the current perpetual (one-time purchase) release. It includes a 5-year support lifecycle ending on October 9, 2029. This is ideal for users who avoid recurring bills.
2. Subscribe to Microsoft 365: This subscription model ensures you always utilize the latest version of Office apps, provided the monthly or annual fee is paid.

Developer and Server Tools Retiring in late 2026

Technical professionals must address the following EOL dates to ensure application stability and server compliance.

• Windows Server 2012 / 2012 R2: The third and final year of Extended Security Updates (ESU) ends October 13, 2026. There are no further extensions. Server migration is now critical.
• .NET 8 (LTS) & .NET 9: Support ceases on November 10, 2026. Developers must retarget applications to .NET 10 (LTS) or a subsequent supported release to maintain security compliance.
• PowerShell 7.4 (LTS): This version reaches end of support on November 10, 2026. Scripts and automation workflows should be tested on newer builds immediately.