I have a new hard drive (Windows 8.1) I was thinking of using Avast. I have heard that MSE is ok. Does that automatically come with Windows or do you have to download it and if it is already built in, would it conflict with Avast?
It comes as part of Windows 8 (but it is now called Defender in windows 8) It will clash with Avast, however when you install Avast (or any other anti virus product) then Windows turns Defender off.