According to Neowin, Microsoft has released a new version of Microsoft Security Essentials (MSE), their free antivirus protection for PCs. It supports:
- Windows XP Service Pack 3 (SP3)
- Windows Vista (Service Pack 1, or Service Pack 2)
- Windows 7
Yes, Windows XP and Windows Vista are both still supported for this new development, even though they are both in extended support. You can understand this exception when you consider the reason for MSE’s existence. It exists to help prevent the spread of malware on PCs that otherwise would not be protected:
- People who get free 90 days of AV with an OEM PC but never buy the subscription
- People who can’t afford to or won’t buy AV
One of the best stories we have of MSE locally was when we did a community launch event for Windows 7 in Belfast. We talked about MSE and how it could help defend against Conficker which was all the rage with unpatched PCs at the time (and unfortunately still is thanks to negligent [IMO] admins/managers). Irish DPE, Dave Northey, saw a photographer was taking photos on behalf of the venue and asked for a copy of some of the photos. The photographer came over at the end of the event with a USB stick. Dave joked that he hoped that Conficker wasn’t on the stick – MSE was on Dave’s laptop and screamed about finding Conficker on the photographer’s USB device 
You might ask about support for Windows 8. Good question. Windows 8 comes with Defender built in (more later). Defender in Windows 8 is not the Defender of old. It actually is anti-spyware and antivirus, meaning that you don’t need to download/install MSE on it.
Built-in AV, eh? Imagine what Symantec’s lawyers, the EU, and so on will think of that! Many of us are presented with a browser chooser when we setup Windows 7 for the first time. I wouldn’t be surprised if we see something similar for AV. Personally, I’d stick with Windows 8 Defender, but there’s nothing to stop you from choosing an alternative. I wouldn’t be surprised if OEMs continue to ship subsidised trial copies of AV and retail stores continue to push AV boxes on customers with their PC/laptop/tablet purchase. You still have a choice, but at least with Windows 8, you have protection by default.