I've recently bought an used mac mini (early 2009 version) patched with preinstalled HighSierra on it. My main goal is to get it working. Currently I'm trying to install El Capitan which is somehow not possible (details below).
It came with firmware password so I cleared it with NVRAM hack. Unfortunately it enabled SIP, so USB is not working after OS boot. It's getting voltage but not operating. Then I started to deal with boot options (order as on apple support page):
- Safe mode - SIP still enabled -> USB not working
- Startup manager - I've created (with
transmac, i will try on another mac with
createinstallmedia) bootable OS X El Capitan USB (with ignore ownership unchecked) -> prohibited.
I've also switched HDD, it turned out it has WinXP installed -> USB not operating
- AHT / Diagnostics not working -> OS booting, no power on USB. Internet AHT -> prohibited.
- NetBoot - don't have one -> skipped
- Recovery. None of the options working, all result in prohibited sign.
- NVRAM / PRAM reset. Yup, I've tried, didn't change anything.
- Single-user mode - Freezes on right after [PCI configuration begin]
- Target disk mode - not needed now, skipped
- Verbose mode - USB not operating, gets to login screen though.
Is anything left I haven't try? Or I would choose having expensive paperweight or letting apple service manage to run this.