So I'm at a dead end right now. My mac randomly shut down and upon rebooting it now is stuck in a Login Loop whenever the password is entered. (I.e the password is entered, I get the spinning beachball, screen goes back, and then it loops me right back to the password login screen). This is the second time that the Mac has randomly shut down and rebooted in the past month. Last time I had to reinstall the OSX from recovery mode, where I got to the apple screen and black text scrolled down the screen and then it would continuously reboot doing the same thing (I think the kernel tasks had crashed?) regardless this is beyond my point and current problem. I'm now stuck on this startup loop and it will not get past the login. I know other users have experienced this, but with their instances they actually got to the desktop screen momentarily before reboot. Mine won't even make it past the login. And if booting in Safe Mode isn't always a miracle option, whenever I boot into Safe Mode, it does the SAME exact thing. I can't get past login on safe mode either. It loops back to login everytime. I've booted into Recovery Mode, and I've used Disk Utility to verify and repair permissions on both drives. Repair completes with no found errors. I've also used Terminal to resetpassword to try to bypass a faulty login keychain. Even a blank login password seems to no avail. I've also reinstalled El Capitan twice from recovery mode and it still won't let me get past login. I have no other usernames or user accounts on the Mac so I cannot try to login to an alternative user account. I have a Genius Bar appointment reserved, but I wish I could figure out how to fix this myself, as waiting for the appointment interferes with getting school work done. I'm working with a 2012? MacBook Pro running El Capitan. This is frustrating and MAY not be related to the update itself, but I've only encountered the problems since upgrading to El Capitan. I'd post more details but I cannot even access "About My Mac". I've read some forums about deleting corrupt .kext files and all the such but those posts went way over my head and I have limited Terminal knowledge.