Microsoft Security Essentials also known as Windows Defender is just no good anymore. I have been recommending it for years now because of how light-weight it is and for the great price of FREE.
Unfortunately, that isn’t the case anymore. The amount of infections that I have been seeing on Windows 7 machines is worse now than ever. While I don’t have hard evidence to support that it is a direct result of MSE not being efficient I can point to numerous instances of terrible infections that had an anti-virus installed.
Certainly the best course of action is to just stop using Windows. We can’t all do that yet and until that day arrives I need to find a way to not spend hours rebuilding infected computers.
As far as recommending a replacement is concern I have only begun to do the research. I do like light-weight and cloud-based security options really entice me on that front. I have installed Panda on a computer recently and I need to figure out a business solution.