MacOS – Yosemite won’t boot in safe mode with Shift held down

bootmacbook promacos

I'm investigating some slowness with my late '13 rMBP which I upgraded to Yosemite on Sunday. Problem is, I can't boot into safe mode by holding the Shift when restarting or powering up.

I tried everything: Pressing and holding it right after I power up, right after I hear the chime, after restarting, after total shut down. Just doesn't work.

Should I be worried?

Best Answer

Ok, I managed to boot to Safe mode using this:

Access the command line by either opening Terminal remotely, or by logging into the computer using SSH.

Use the following Terminal command:

sudo nvram boot-args="-x"

If you want to start in Verbose mode as well, use sudo nvram boot-args="-x -v" instead.

After using Safe Mode, use this Terminal command to return to a normal startup:

sudo nvram boot-args=""

Yosemite is looking more worrisome by the hour though.

Related Question