I took the CS6 master collection off of my computer once I started subscribing to CC for photographers. I recently added Premiere and After Effects from my CS6 back onto my computer and, while Premiere loaded without a problem, After Effects won't load. I get the message "You can't use this version of the application "Adobe After Effects CS6" with this version of OS X." (I have OS X El Capitan). I'm not sure what that means? What version do I need?
Run the updater. You need version 11.4, which was the last CS6 update.