Windows 10 Security Updates Just Ended: What Your Business Should Do

If your office still has a few Windows 10 computers humming along, this month is a turning point. Microsoft officially ended regular support for Windows 10 back in October 2025, but many people kept getting security fixes through a one-year program called Extended Security Updates, or ESU. For home and small-office PCs enrolled through the consumer version of that program, those updates stopped on October 13, 2026.

The computers still turn on. Your programs still open. Nothing dramatic happens on the screen. That is exactly why this deadline is easy to miss, and why it matters.

What "no more security updates" really means

Every month, Microsoft fixes security holes that criminals have found in Windows. These fixes are called patches. When a computer stops getting patches, every new hole discovered from now on stays open on that machine for good.

Attackers know this. They actively look for computers running unsupported systems, because one weak PC can be the doorway into the rest of your network: shared files, email, accounting software and backups.

Your antivirus helps, but it cannot fix a flaw in Windows itself. (We covered why in our article "I Have Antivirus. Why Do I Still Get Viruses?") An unpatched operating system is like a lock that everyone knows how to pick.

Step 1: Find out which computers are affected

Before you can make a plan, you need a list. On each computer:

1. Press the Windows key and type winver, then press Enter.
2. A small window shows the version. If it says Windows 10, write down the computer's name, who uses it, and roughly how old it is.

Don't forget the machines people overlook: the front-desk PC, the computer attached to the label printer or shop equipment, a laptop in a drawer that comes out twice a year, and any older server in the back closet.

Step 2: Decide what to do with each one

For most businesses, every Windows 10 machine falls into one of three groups.

Upgrade it to Windows 11

Many computers bought in the last several years can run Windows 11. To check, open Settings, go to Windows Update, and look for a message about Windows 11. Microsoft's free PC Health Check app can also tell you whether a machine qualifies.

Before upgrading, make sure your important programs work on Windows 11 (most do, but older accounting, design or industry-specific software is worth confirming), and back up the computer first.

Replace it

Computers that can't run Windows 11 are usually older machines that were nearing retirement anyway. If you were already planning end-of-year purchases, now is a good time to put these at the top of the list. When you replace a computer, plan for moving the user's files, email and settings, and for wiping the old drive properly before it is recycled or donated.

Extend it, as a short-term bridge

Microsoft also sells a paid ESU program for businesses, offered one year at a time for a limited number of years. If you have a machine that truly can't be upgraded or replaced yet, for example because it runs one piece of software that won't work anywhere else, this can buy time. Treat it as a bridge with an end date, not a permanent fix.

Step 3: Protect yourself while you transition

Upgrades and replacements don't happen overnight. In the meantime:

• Keep up-to-date backups. If an older machine is compromised or simply fails, a good backup is what gets you back to work.
• Limit what old machines can reach. Avoid using an unsupported PC for email, web browsing or online banking.
• Keep browsers and programs updated on every machine, even while Windows itself is not.
• Watch for scams that use the deadline. Be wary of pop-ups, calls or emails claiming your "Windows license has expired" or offering to "fix" your computer. Microsoft does not call you out of the blue.

Looking ahead: older servers too

If your business runs its own server, check what version of Windows Server it uses. Microsoft has announced that support for Windows Server 2016 ends in January 2027. If that's what is in your closet, it is worth planning now rather than in a rush after the holidays.

A computer that still works isn't the same as a computer that is still safe.

We can help you sort it out

You don't have to work through this list alone. GNTI has been helping businesses around the Puget Sound keep their computers secure and running since 1999. We can take inventory of your machines, tell you which ones can be upgraded, help you plan replacements, and make sure your data is backed up before anything changes.

Learn more about our Managed IT Services and Data Backup, or contact us to talk through your Windows 10 plan. Call Seattle at 206.569.4684, Tacoma at 253.267.6727, or email support@gnti.com.