My 2009 iMac (El Capitan 10.11.6) is currently running off a 6TB external drive. How do I make it so it will run off its own 1TB internal drive? When I select the startup disk in system preferences I cannot see another option. The 1TB drive is enough to sustain the OS and my files so I'd like to get the 6TB drive back for other duty. Any help would be greatly appreciated.
iMac, OS X 10.11
System Preferences > Startup Disk. Unlock, choose the internal and restart.
If the internal drive is not there, open Disk Utilities and look for it there. If not mounted, mount it and reboot, then do the startup disk selection.
Sitting unused should have not damaged it, but it may be damaged, in need of first aid or in need of reformatting. Only you know what condition it was in when you switched.
System Preferences > Startup Disk. Unlock, choose the internal and restart.
If the internal drive is not there, open Disk Utilities and look for it there. If not mounted, mount it and reboot, then do the startup disk selection.
Sitting unused should have not damaged it, but it may be damaged, in need of first aid or in need of reformatting. Only you know what condition it was in when you switched.
Try this when pressing the start button.
Press and hold Option (⌥) or Alt: Start up to Startup Manager, which allows you to choose other available startup disks or volumes. If your Mac is using a firmware password, you're prompted to enter the password.
The disk utility app worked. Thank you for pointing me in the right direction.
How to Startup from internal drive when external startup is no longer desired?
