Microsoft puts Windows 10 installer on PCs even if you don't ask for it
Taking the idea of "automatic updates" to the extreme, Microsoft has confirmed that it's downloading Windows 10 installation files on PCs just in case you might want to upgrade, The Inquirer reports. As a Microsoft rep tells it, the company is placing the files on computers that have opted into automatic updates through Windows Update. Normally that just entails getting a few security fixes every few weeks, but the Windows 10 installer can take up around 3.5GB and 6GB on your system. That's a lot of precious hard drive space for something you might not even want (though it's definitely worth upgrading). Microsoft probably figures it's worth preloading files to make the Windows 10 installation faster, but it seems like a boneheaded move when storage is scarce on some machines (especially if you're stuck with flash memory or a small SSD). It makes more sense for Microsoft only to preload the files after you've decided to "reserve" the free upgrade.
http://www.engadget.com/2015/09/11/windows-10-preload/
