Three Microsoft cut-offs land in October 2026
The short version
Three separate Microsoft deadlines arrive within a few weeks of each other. They affect different things, they have different fixes, and only one of them announces itself.
| What | Date | Who it hits |
|---|---|---|
| Windows 11 version 24H2 stops getting updates | 13 October 2026 | Home, Pro, Pro Education and Pro for Workstations |
| Office 2021 support ends | 13 October 2026 | Anyone who bought Office once, rather than subscribing |
| Exchange Web Services starts being switched off | October 2026 | Older software that connects to a Microsoft 365 mailbox |
None of these stops a computer working the next morning. Two of them quietly stop security updates, and the third can break a booking system or a customer database without touching Outlook at all.
This page is the check list, not a sales pitch. Most of it you can do yourself in an afternoon.
1. Windows 11 version 24H2 stops getting updates
A version of Windows 11 is supported for a fixed run, not forever. Microsoft's release information gives version 24H2 an end of updates date of 13 October 2026 for Home, Pro, Pro Education and Pro for Workstations (Windows 11 release information).
Enterprise and Education editions of the same version run a year longer, to 12 October 2027. That difference matters, because a business laptop and a home laptop can be on the identical build and have different deadlines.
What to check. Press the Windows key, type winver and press Enter. A small box tells you the version. If it says 24H2, you have until October. If it says 25H2, you are supported to 12 October 2027.
What to do. Let Windows Update install the newer version. This is a version update on the same computer, not a new machine and not a reinstall. If a machine keeps refusing the update, that is worth looking at properly, because it usually means a driver, a disk space problem or an old storage controller rather than a hard block.
One caution. There is also a version 26H1, and Microsoft says it is scoped to new devices coming to market and is not offered as an in place update from 24H2 or 25H2. Do not go looking for it on an existing machine.
2. Office 2021 support ends, with nothing after it
If you bought Office once, as a one off purchase rather than a monthly subscription, this is the one to read. Microsoft's lifecycle announcement is titled plainly: Office LTSC 2021 reaching end of support on 13 October 2026 (Microsoft lifecycle announcement, product lifecycle record).
Two details matter more than the date.
The first is that there is no paid extension. Windows got an extended security updates programme; Office 2021 does not. When it ends, that is the end.
The second is that Word and Excel keep opening. Nothing deletes itself, no file becomes unreadable, and the apps do not stop on the day. What stops is the security fixes. So this is not an emergency, it is a decision you should make on purpose rather than discover in a year when something goes wrong.
What to check. Open Word, then File, then Account. It will say either Microsoft 365 or a one off product name with a year in it.
What to do. If you are on a one off 2021 licence, plan the move now while nothing is broken. That is either a Microsoft 365 subscription or a newer one off version. Which one is right depends on how many people you have, whether you need the mailbox side, and whether you want a monthly cost or another lump sum. Worth twenty minutes of thought rather than a rushed purchase in October.
3. The one that breaks things quietly: Exchange Web Services
This is the item most small businesses will not see coming, because it has nothing to do with the computer in front of you.
Exchange Web Services is an old way for other software to talk to a Microsoft 365 mailbox. Microsoft's guidance states it plainly: October 2026, EWS starts to be disabled globally for all organizations, and April 2027, EWS is fully disabled (Microsoft EWS deprecation guidance).
Microsoft also widened the scope of that work from other companies' software to its own products, and points administrators at usage reports that show which applications are still using it.
Why you should care. Outlook will be fine. What can stop is the thing you forgot connects to your mailbox: an older booking system, a customer database that files emails against a job, a practice management system, a scanner that sends to a mailbox, a bit of accounting software that reads appointments. When it breaks, the symptom is not an error message. It is that something stopped syncing and nobody noticed for a fortnight.
What to do. Write down every piece of software that touches your mailbox or calendar. For each one, ask the vendor a single question: does your product still use Exchange Web Services, and if so what is your timeline. Their answer is the whole story. If a vendor cannot answer that in September 2026, treat that as information about the vendor.
An administrator can also check Microsoft's own EWS usage report to see what is actually connecting, which beats guessing.
Still on Windows 10?
The obvious next question, since it changes whether you replace a machine at all.
Windows 10 ordinary support ended on 14 October 2025. Microsoft's consumer extended security updates programme continues to provide critical and important security updates, and you can enrol at any time until the programme ends on 12 October 2027. If you are already enrolled, coverage continues to that date automatically (Microsoft extended security updates).
Two limits are worth knowing before you rely on it.
It is security updates only. Microsoft says it does not include other fixes, feature improvements or product enhancements, and it does not come with technical support.
It is a consumer programme. Microsoft states it cannot be used in commercial scenarios, and that enrolment is not offered for devices in kiosk mode or joined to a domain or Microsoft Entra, or enrolled in mobile device management. In plain terms: the home laptop can use it, and the properly managed office fleet needs the business route instead.
What to actually do this month
- Run
winveron each machine and write down the version. That one word decides whether October matters for it. - Check Word under File then Account and note whether each machine is subscription or a one off 2021 licence.
- List every piece of software that connects to your mailbox or calendar, then email each vendor the Exchange Web Services question.
- Separate the software decision from the hardware decision. A machine that needs a Windows version update is not the same as a machine that needs replacing, and the two get confused every October.
- Check your backup restores before you change anything on a machine that matters. Not that the backup ran. That a file comes back.
Nothing here needs to be finished this week. All of it wants to be finished before October.
Ask us to check your machines and mailbox connections
Frequently asked questions
Will my computer stop working on 13 October 2026?
No. Nothing switches off. Windows keeps booting and Office keeps opening. What ends is the flow of security updates, which is a risk that builds over months rather than a failure on the day.
Do I have to buy a new computer?
Usually not for these dates. A Windows 11 machine on version 24H2 needs a version update, which is free and happens through Windows Update on the same hardware. Replacement is a separate question about the machine's age, speed and whether it can run what you need.
What is the difference between Windows 11 24H2 and 25H2?
They are versions of the same Windows 11, released about a year apart, each with its own support run. Version 24H2 Home and Pro end updates on 13 October 2026, and version 25H2 Home and Pro run to 12 October 2027. Checking with winver takes five seconds and tells you which clock you are on.
Is there a paid extension for Office 2021 like there is for Windows 10?
No. Windows 10 has a consumer extended security updates programme running to 12 October 2027. Office 2021 has no equivalent, so its October date is the end of updates rather than the start of a paid extension.
How do I know if anything of ours uses Exchange Web Services?
Start with the list of software that touches your mailbox or calendar and ask each vendor directly. An administrator can also look at Microsoft's EWS usage report in the admin centre, which shows what is actually connecting rather than what you remember installing.
We are a small business still on Windows 10. Can we use the consumer extended updates?
Microsoft says the consumer programme cannot be used in commercial scenarios, and it is not offered for devices joined to a domain or Microsoft Entra, or managed through mobile device management. A home machine can usually enrol. A managed office fleet needs the business path instead.
Everything still works. Why do this now rather than in October?
Because the only one that breaks something is the mailbox connection item, and that one is answered by vendors, not by you. Vendor answers take weeks. Doing the asking in September means October is paperwork.