I am having a heck of a time trying to download Mac OS X Yosemite on this network. I am fairly new here and am not a Mac person. That's two strikes. After researching this procedure it seems pretty straightforward. The first little difference in my research and what I see on the App Store is that there is no "download" button available for me. But there is the little "Free" button. If I click on the "Free" button she just sits there and spins for hours and nothing shows up as being downloaded? We have a proxy server here, so this might be the cause. Not sure? Our proxy server is configured in the System Preferences/Network/Advanced section, but that doesn't seem to get the App Store app through. I am just speculating as I have stated I am not a Mac person. Any help with this would be greatly appreciated. I am running an iMac 27 with 10.6.8 Snow Leopard.