How do you remove the original owner (administrator) on a MacBook (OSX, 10.9.5)?
My son gave it to me when he upgraded to a newer one. I currently am assigned administrator, but he keeps popping up and I have to keep changing my Apple ID password.
iPad, Windows 7
Your son should have followed the instructions here:
What to do before selling or giving away your Mac - Apple Support
OS X 10.9 was Mavericks. So follow the directions for Mavericks above, and then install the current OS X (El Capitan):
Ideally you'd want to do a clean wipe and reinstall of OS X and update to El Capitan if the Mac model supports it. Before handing it off the original owner would want to log off iCloud and deauthorize the iTunes account. If required your son can go to iCloud.com, login with his id, go to settings, locate the Macbook and follow the process to remove it from his ID. These links might be helpful.
What to do before selling or giving away your Mac - Apple Support
my son gave me his MacBook when he bought a new one and I need to know how to get him off as administrator
