If you corrupt the nvram with the wrong code, it can leave your Mac unbootable and Command+Opt+P+R doesn't work.
Here is what you do:
For desktops, just hold the power button, and keep holding......You'll hear the programers tone, keep holding, you'll hear a boot chime, then the system will enter Open Firmware with the defaults loaded. Now just reset the nvram.
New World:
For Portables, hold Power and Apple Key, keep holding, you'll hear the programers tone, keep holding, you'll hear a boot chime, keep holding, the system will enter Open Firmware and you can reset the nvram.
This will likely work to bypass an Open Firmware password.
I'll test it and get back to you.
[doublepost=1545596925][/doublepost]If you happen upon an iBook/Powerbook that someone other than you set the Firmware Password, here is what works for me on my iBook6,7( 2005 ). Should work on other iBooks and Powerbooks, and maybe desktop systems( untested ).
1. Remove the Battery.
2. Disconnect the power adapter.
3. Remove a stick of Ram.( or skip to sept 4 if you have no ram sticks to remove ).
4. Reconnect the Power adapter.
5. Power on the system holding Command+OPT+P+R( If the system boots, power it down, however if you hear more than one boot chime, you are done, the nvram has been reset, and the password has been cleared. )
6 Power down the system.
7. Disconnect the Power adapter.
8. Add a stick of ram back to the system.
9. Connect the Power adapter.
10. Power on the system holding Command+OPT+P+R( Wait until you hear three boot chimes ).
It took all ten steps for me, when I removed a stick of ram and tried resetting the nvram, it didn't work, just booted my startup disk. However when I added the ram back to the system and powered it on, I was able to clear the NVRAM and get rid of the Firmware password.
For portables, don't forget to remove the battery, or it won't work.
[doublepost=1545597318][/doublepost]Also tested on an iBook G3 600Mhz, steps 1-5 worked.
Here is what you do:
For desktops, just hold the power button, and keep holding......You'll hear the programers tone, keep holding, you'll hear a boot chime, then the system will enter Open Firmware with the defaults loaded. Now just reset the nvram.
New World:
Code:
reset-nvram
reset-allFor Portables, hold Power and Apple Key, keep holding, you'll hear the programers tone, keep holding, you'll hear a boot chime, keep holding, the system will enter Open Firmware and you can reset the nvram.
This will likely work to bypass an Open Firmware password.
I'll test it and get back to you.
[doublepost=1545596925][/doublepost]If you happen upon an iBook/Powerbook that someone other than you set the Firmware Password, here is what works for me on my iBook6,7( 2005 ). Should work on other iBooks and Powerbooks, and maybe desktop systems( untested ).
1. Remove the Battery.
2. Disconnect the power adapter.
3. Remove a stick of Ram.( or skip to sept 4 if you have no ram sticks to remove ).
4. Reconnect the Power adapter.
5. Power on the system holding Command+OPT+P+R( If the system boots, power it down, however if you hear more than one boot chime, you are done, the nvram has been reset, and the password has been cleared. )
6 Power down the system.
7. Disconnect the Power adapter.
8. Add a stick of ram back to the system.
9. Connect the Power adapter.
10. Power on the system holding Command+OPT+P+R( Wait until you hear three boot chimes ).
It took all ten steps for me, when I removed a stick of ram and tried resetting the nvram, it didn't work, just booted my startup disk. However when I added the ram back to the system and powered it on, I was able to clear the NVRAM and get rid of the Firmware password.
For portables, don't forget to remove the battery, or it won't work.
[doublepost=1545597318][/doublepost]Also tested on an iBook G3 600Mhz, steps 1-5 worked.
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