My first attempt to upgrade from yosemite to el capitan, was a failure. Black screen with apple logo, and the progress bar stuck. I restored my mbp back from a bootable image. I installed el capitan from a bootable usb flash disk, created from me with 'diskmakerx'. So, with this way, I passed to el capitan. Now, I try to upgrade to 10.11.1. Same bad thing. Black screen with apple logo, and the progress bar stuck. I have to restore back to 10.11, in order to have a working computer. Some users here told me to uninstall handsoff firewall. I did it. Completely uninstall. It didn't help. I also run 'etrecheck' in order to find any problematic or obsolete elements in my system. Nothing 'red' - dangerous mentioned by the program. Take a look at 'what's new' in 10.11.1: 'improves installer reliability when upgrading to osx el capitan'. But the improvement is zero! So, where is the problem? Why, as a mac user, I cannot upgrade to anything related to el capitan? I suspect apple's poor 'installer', but, I want to be sure. I want to be able to make updates! Please, help me solve this serious problem.