I have a Macbook Pro 15 inch 2009 running OS X 10.10.2. I want to update the OS to El Capitan but the App Store won't open - nor will Safari, Contact, Calendars etc. Chrome seems to be one of a handful of the apps that are opening fortunately.
I've already tried the following:
1 - Opened
Library/Preferences/com.apple.appstore.plist and deleted it
2 - As above but for Safari because apparently Safari, App Store and iTunes share the same history and preferences?
3 - Created another user but encountered the exact same problem.
4 - Tried running this command on iTerm (because Terminal wouldn't run either)
softwareupdate -a -i
but this failed because I don't have the correct permissions. On this one I was logged in as an Admin and also tried starting a bash command with
sudo -s but it didn't output anything.
5 - I attempted to start Mac OS Recovery but holding cmd+r on startup but it's asking for a password but none of the passwords for any of the admin accounts work.
What else can I possibly try short of ordering recovery disks or saying screw it and buying a new Macbook altogether (which I really don't want to do!)