Q: OSX stuck somewhere between Yosemite & El Capitan
So, I tried to upgrade to El Capitan and my iMac hung up, had to shut down. Gets stuck early in process and hangs, have read numerous posts on that.
After shutting down, i could not start up normally, as it would not see operating system and try to install El Capitan with same hanging result.
Could not boot into safe mode - hangs at "checking catalog file". Boot into recovery mode to try to reinstall osx, and it is trying to reinstall El Capitan. Tried disk utility First Aid for Macintosh HD in recovery mode, and this also hangs at "Checking Catalog Hierarchy".
I tried normal boots several times until it actually booted up - system indicates it is running Yosemite. System is slow and having problems. Ran disk verify and repair, fixed disk permissions.
I want to get the system running better, so I am simply trying to simply re-install Yosemite at this point. Remember, I can't do this from recovery because recovery thinks I have El Capitan.
I have made a bootable Yosemite install USB drive. Question is, if I re-install from this USB, will it completely overwrite everything on Macintosh HD? Or will my files there be ok and it will only overwrite osx system files? I know you can do a non-destructive reinstall of OSX from recovery, but I do not see an answer for re-installing from a bootable USB.
Need to know so I can take steps if necessary - one of the components not working since my attempted upgrade is Time Machine.
TIA for any help and guidance
iMac (21.5-inch Mid 2011), null
Posted on Aug 3, 2016 1:46 PM
If the system indicates it is running Yosemite and you boot off a Yosemite install USB drive, it shouldn't erase the drive because you are replacing the OS with the same OS. Do a backup, preferable 2 separate ones on 2 drives.
On your second question, if you do a clean El Capitan install, your will have to restore your data from your backup. If you reinstall Yosemite successfully and then upgrade, you won't have to restore your data.
Posted on Aug 4, 2016 11:01 AM