Windows 10 support ended, but our computers still work fine. What are we actually risking by keeping them?

It is a fair question, because nothing dramatic happened. Microsoft ended standard support for Windows 10 in October 2025, and every Windows 10 machine kept right on turning on, running QuickBooks, and printing invoices. That experience convinces a lot of owners the deadline was hype. It was not. It just was not the kind of deadline where things visibly break.

Here is what actually changed: an unsupported computer stops being defended. When researchers or criminals find a new hole in Windows 10 now, Microsoft does not fix it for free anymore. That hole stays open on your machine permanently, and the list of open holes only grows. Attackers know this, and their automated tools specifically scan for aging, unpatched systems because they are the easy wins.

For a business, one old machine is rarely just one old machine. It sits on the same network as everything else, so a single unpatched front-desk PC can be the entry point that reaches your file server, your accounting system, or your practice management software. There are quieter costs too: compliance frameworks expect supported, patched systems, and cyber insurance applications now commonly ask point-blank whether you run unsupported operating systems. Answering that wrong, or not knowing the answer, is a bad place to be after an incident.

None of this calls for panic. It calls for a list and a plan: inventory your Windows 10 machines, upgrade the ones that qualify for a free move to Windows 11 (roughly 2019 and newer often do), phase replacements for the rest, and use Microsoft's paid Extended Security Updates deliberately as a bridge for the few machines that truly cannot move yet. A calm plan now beats an emergency later, and the window for calm planning is still open.