Sometimes I wish Apple had not found such success with iPhone and other gadgets, so that it would remain focused on Macintosh and Mac OS X. This morning I saw that OS X 10.11.5 was released and so I dutifully went to install it. My MacBook is now trapped in an endless loop where the startup chime plays, the Apple logo shows together with a progress bar showing about 60% completion, and then the screen goes black and the machine restarts. Every five seconds or so, the startup chime plays again and there's a reboot. Thanks, Apple!