Microsoft antivirus no longer supports XP, AVG anti-virus no longer supports XP, AVAST no longer supports XP, etc. Most no longer support Windows 7 either.
As such some of our clients, of our point of sale software are running into a problem that old versions of windows are no longer supported and now it appears that most of the antivirus companies are not supporting XP either. This leaves them open to most viruses and ransomware.
For these users, I am recommending
Details here
It is a free product for commercial use, it has no licenses, no expiration and no hidden fees. It is also a first-class product which runs on just about any computer and is fast.