So I just updated my Early 2011 MacBook Pro to from the last Yosemite build to the latest 10.10.5 and a strange glitch happened. My Mac shut down all of my applications like normal and restarted. The installation begin and then restarted upon completion. Then, a white screen with a large blank loading bar appeared. A few second later it restarts again with the loading bar. It continued to do this in an endless cycle until I force shut down and turned the machine back on. Upon powering up, it proceeded to complete the installation and started up normally. I've checked on "About my Mac" and I've confirmed it's on 10.10.5. I just thought that was a bit strange. Anyone else had this happen to them or have any idea what it was? UPDATE: According to someone on reddit, it actually fully borked their 2010 iMac and they are now having to reinstall from recovery partition.