error code -600
What is error code -600 and how do I get rid of the problem.
iMac, OS X 10.10
If I read that & other thread about it,it requires a reinstall of the OS..
Start with this...
Safe Boot, (holding Shift key down at startup). Could take 10 minutes.
Safe mode attempts to repair Disks & clears lots of caches & loads safe Drivers, & prevents loading of 3rd party extensions.
Then...
Start up from macOS Recovery
To start up from macOS Recovery, turn on your Mac and immediately press and hold ...
Command (⌘)-R
Installs the latest macOS that was installed on your Mac.