Editted my com.apple.boot.plist, now my Macbook won't boot.

[Adamantoise]

I get this message ...

"You need to restart your computer. Hold down the Power button until it turns off, then press the Power button again."

I kept trying to boot OS X Lion (10.7.2) into 32 bit mode (needed to install GPIB drivers for NI LabView), but nothing seemed to work.

I tried the rebooting while holding "3" and "2" ... I even tried the sudo command. Nothing worked. Lastly I resorted to editing my com.apple.boot.plist ... Now every time I start my computer I am faced with this message.

Is there any way to undo this?

 

[pscraig]

This is called a kernel panic. Try holding down cmd+S while booting to boot into single user mode.

Just for kicks try holding down 6 and 4 while booting to force the native 64 bit kernel.

If you have another hard drive with a bootable OSX installation, boot from it and then access your hard drive as an external drive, and edit the plist back to its original state. If you know someone else with a Mac running Lion you could connect your Macs via Firewire and access your drive over target disk mode.

If all this does not work, I suspect you will need to reinstall OSX.

 

[negativzero]

I get this message ...

"You need to restart your computer. Hold down the Power button until it turns off, then press the Power button again."

I kept trying to boot OS X Lion (10.7.2) into 32 bit mode (needed to install GPIB drivers for NI LabView), but nothing seemed to work.

I tried the rebooting while holding "3" and "2" ... I even tried the sudo command. Nothing worked. Lastly I resorted to editing my com.apple.boot.plist ... Now every time I start my computer I am faced with this message.

Is there any way to undo this?

Boot into recovery mode and use Time Machine. If you don't have a Time Machine backup sorry then but you're screwed.

 

[Adamantoise]

Thanks guys, but I managed to figure it out.

I just held down "6" and "4" to boot into 64 bit mode again, at which point I made sure to revert the com.apple.boot.plist file to it's original setting.

Question though ... Why can't my machine boot in 32 bit mode?

Edit: Incidentally, that's what pscraig recommended haha.

 

[maflynn]

Why would you want to run 32bit anyways

 

[Adamantoise]

Why would you want to run 32bit anyways

Do people not read posts before replying them anymore?

I clearly stated that I need certain LabView drivers installed (GPIB and VISA) ... You think I'm just going to wake up one morning and run 32 bit because I'm bored?

I need this for my one of my graduate classes, I would rather do my work at home instead of having to drive to the lab in the snow to use the computers there.

That is why I need to run 32 bit once in a while. Does anyone know how to boot into 32 bit mode without a kernel panic?

 

[maflynn]

Do people not read posts before replying them anymore?

I clearly stated that I need certain LabView drivers installed (GPIB and VISA) ... You think I'm just going to wake up one morning and run 32 bit because I'm bored?

Sorry I missed that

Did you try just running to see if you select it to run in 32bit mode, highlight the app, hit ctrl-i and check the "Open in 32-bit mode" check box

 

[Nermal]

Change back to 32-bit mode and hold Cmd-V to get a boot log. You can then see where it's failing (you may need to post a photo of this screen).

Incidentally you can update the plist by typing "sudo systemsetup -setkernelbootarchitecture i386" rather than doing it by hand ("sudo systemsetup -setkernelbootarchitecture x86_64" to change back).

Edit: I forgot to ask: Have you already installed the drivers or is this a "clean" system?

 

[Mr. Retrofire]

Do people not read posts before replying them anymore?

Obviously not. They think they know everything.

I need this for my one of my graduate classes, I would rather do my work at home instead of having to drive to the lab in the snow to use the computers there.

That is why I need to run 32 bit once in a while. Does anyone know how to boot into 32 bit mode without a kernel panic?

Commands for the Mac OS X Terminal.app:

sudo systemsetup -setkernelbootarchitecture i386

activates the 32-Bit kernel (requires a reboot).

sudo systemsetup -setkernelbootarchitecture x86_64

activates the 64-Bit kernel (requires a reboot).

 

[Adamantoise]

About those terminal commands, anytime I try to execute one of them, I am shown a message in the terminal prompt saying "No valid sudoer sources found ... quitting"

How do I get sudo privileges or use sudo commands? I'm not very familiar with the command line interface.

Thanks!

 

[Nermal]

That's not good!

Are there any other messages or just that one?

 

[Adamantoise]

Change back to 32-bit mode and hold Cmd-V to get a boot log. You can then see where it's failing (you may need to post a photo of this screen).

Incidentally you can update the plist by typing "sudo systemsetup -setkernelbootarchitecture i386" rather than doing it by hand ("sudo systemsetup -setkernelbootarchitecture x86_64" to change back).

Edit: I forgot to ask: Have you already installed the drivers or is this a "clean" system?

Well I booted to 32 bit successfully the first time I tried to install the VISA driver (checked by making sure the kernel_task was in 32 bit), and it told me it succeeded the installation but required a reboot.

Ever since then, every time I try to boot in 32 bit I am getting kernel panics.

Is there something I am missing to successfully boot into 32 bit mode? Everywhere I look makes it sound like it's supposed to be easy, I really have no idea what I am doing wrong.

----------

Sorry I missed that

Did you try just running to see if you select it to run in 32bit mode, highlight the app, hit ctrl-i and check the "Open in 32-bit mode" check box

It's a driver not an application. You can't just run a driver in the mode of your choice.

Drivers are specifically written for certain architectures, this is why you often see 32 bit driver and 64 bit driver when you visit a support page for any hardware.

 

[Mr. Retrofire]

How do I get sudo privileges or use sudo commands? I'm not very familiar with the command line interface.

If you are not an admin-user you can obtain sudo privileges via the login command (in the Terminal):

login ShortFormOfAdminUserName

for example:
login adam

The login command asks you for an admin password.

Then use the sudo command as necessary. A standard user name & password are not enough.

 

[Adamantoise]

If you are not an admin-user you can obtain sudo privileges via the login command (in the Terminal):


for example:
login adam

The login command asks you for an admin password.

Then use the sudo command as necessary. A standard user name & password are not enough.

Thanks! I was able to use the login command successfully.

However, upon trying "sudo systemsetup -setkernelbootarchitecture i386" ... I am still shown the error messages:

sudo: can't open /private/etc/sudoers: Permission denied
sudo: no valid sudoers sources found, quitting

In that order, any idea why I am being denied permission?

 

[Nermal]

Try doing a permission repair in Disk Utility. I'm not sure whether it touches that particular file, but it's worth a shot.