Need to do a clean reinstall of El Capitan. What files do I backup first so I don't lose any personal data?
I need to do a clean reinstall of El Capitan on a partition of an external drive where it was originally installed but has now become corrupted. The partition will not boot nor can it be repaired in D.U.
I intend to wipe the partition clean and then clone onto it a pristine bootable version of Mac OS 10.6.8 after which I plan to update to El Capitan using the same El Capitan installer that I used for my original installation of El Capitan (from Snow Leopard).
I realize I need to back up my old (now corrupted) install of El Capitan before I wipe the partition clean so I don't lose any personal data or files. Intend to use Carbon Copy Cloner for that. My question is exactly which files do I back up and which do I tell CCC to ignore? And then how do I restore them to the partition that will now have a fresh install of El Capitan on it?
iMac 21.5″, OS X 10.11