I have recently installed Microsoft Security Essentials (MSE) on Windows 7. To my surprise, I discovered that updates are delivered not just when requested via MSE but also as an optional update via Windows update. I have downloaded some through Windows update but that seemed to cause a few problems - Windows update stopped working (error code 80244019), for example. That probem has now been sorted out, but I still wonder why these MSE updates appear in Windows update as optional updates. Should one simply ignore them and download using MSE instead?