Yesterday I downloaded Microsoft Security Essentials. I also inadvertently started to download a free games site which I thought I had stopped until it came up on screen when I started my laptop. On trying to find it to delete it I found the Windows Defender was turned off. A box comes up saying it is turned off. I click to turn it back on again and nothing happens. I cannot even get rid of the box and have to remove it by Task Manager. So, is it the Microsoft Security Essentials or the free game site that has caused the problem and how do I resolve it please?

Microsoft Security Essentials incluses its own robust anti-spyware utility. Thus, the native Windows Defender is turned-off to avoid conflicts and/or error messages. Please review: Microsoft Security Essentials vs. Windows DefenderCarey Frisch