cooperlulu Said:
"OS High Sierra (10.13.6): I want to erase all content in my mid-2011 iMac before deposing the unit. I followed steps as suggested but still failed. The machine was just hanged (for hours) while i was trying to enter into the recovery mode by turning on the machine and immediately pressing & holding: Command and R."
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Boot in Safe Mode, First:
In Safe Mode, login item do not load at login, certain System Preferences are set aside, and damaged system files (i.e. caches) are fixed.
- Hold Down: shift key, upon boot
- Log in: for 30 seconds.
- Restart: normally
- Log in: for 30 seconds
- Boot in: Recovery Mode
- Try: this once more