If you have problems downloading software updates from the App Store:

I had an issue downloading the new version of OSX El Capitan released 19JAN2016. I simply downloaded it from the Downloads link associated with the operating systems. It WILL download this way. After your Mac start back up you will then click on your user name if you are the administrator, and then the progress bar of death comes. BE PATIENT!! It may seem like the download has froze completely. After numerous times restarting, I realized patience works best. The status then went to the big colorful X "Completing Installation".