Most business owners think of Windows 11 as one thing. You moved off Windows 10, so you're current. Done.
It isn't quite that simple. Windows 11 comes out in yearly versions, and each one only gets security updates for a limited time. A computer can say "Windows 11" on the screen and still be running a version Microsoft has stopped patching.
That just happened to a lot of PCs.
What changed in October 2026
Microsoft released Windows 11 version 26H2 on September 29, 2026. Two weeks later, on October 13, version 24H2 received its last security update for the Home and Pro editions, which are what most small businesses run.
Here is where each version stands today for Home and Pro:
26H2: supported until October 2028
25H2: supported until October 2027
24H2: ended October 13, 2026
23H2 and older: ended earlier
So if a PC in your office is on 24H2 or anything older, it has been without security fixes since mid-October, and it will keep falling further behind each month.
If you run the Enterprise or Education editions, 24H2 is covered until October 2027. Most small offices don't.
Why this matters more than it sounds
Unpatched means exposed. New weaknesses in Windows are found every month. Supported versions get the fix. Unsupported ones don't, and attackers know exactly which holes are open.
Insurance questions. Cyber insurance applications commonly ask whether your systems receive security updates. "It's Windows 11" isn't the same as "yes."
It's invisible. Nothing on the screen warns you in big letters. The PC works the same as it did the day before.
Check any PC in two minutes
Press the Windows key, type winver, and press Enter.
A small window opens. Look for the line that says Version.
If it says 25H2 or 26H2, that computer is fine. If it says 24H2, 23H2, or older, it needs updating.
You can also find it under Settings, then System, then About, in the "Windows specifications" section.
Do this on every computer, including the one in the back office that nobody thinks about.
How to get current
Open Settings, go to Windows Update, and select Check for updates. If a newer version is offered, you'll see an option to download and install it.
Some good news: for a PC already on 24H2, moving to 25H2 or 26H2 is a small update. It typically takes a few minutes and one restart. A PC on 23H2 or older has a bigger jump and can take an hour or so, so do those at the end of the day.
Why a PC gets stuck on an old version
If the update isn't being offered, it's usually one of these:
Updates were paused at some point and never turned back on.
The computer rarely restarts. Updates download but never finish installing.
The drive is nearly full. Windows needs free space to update.
Microsoft is holding it back because of a known problem with a driver or program on that PC. These holds are usually lifted once the conflict is fixed, sometimes by updating that one program.
A setting from a previous IT provider is deferring updates, and nobody remembers it's there.
Make it a habit
Windows 11 gets a new version every fall, and an older one drops off around the same time. The check you just did is worth repeating every October. Put it on the calendar.
How HonIsT Solutions can help
For our clients, this isn't a once-a-year scramble. We keep a live inventory of every computer, including the exact Windows version it's running, so we know which machines are about to fall out of support before it happens. We schedule the updates after hours, sort out the ones that get stuck, and confirm afterward that every PC is actually current.
If you checked a few computers and found some on 24H2 or older, book a 15-minute call. We'll tell you what we'd do, and how long it would take to get everything current.