iMac 27” boot problem
My iMac, old tho it is, still does every thing I need.
(OK, it’s oldish 2008).
The internal hard disc went bad long time ago. So since then I have used an external USB disc as Mac OS, which worked OK.
But the external Mac OS disc has now seemed to go bad. So Used CMD R and retrieved a back up (from a different USB disc) to another different USB disc (erased before backup restore). After ward checked it with First Aid - all OK.
Now, when I re power the IMac it fails to boot and, after much time, ends in displaying ‘apple.com/support error -2003F.
Pls help. How do I tell it which disc to boot from??
Earlier Mac models