Resetting default system boot

[N3m35i5]

Can anyone explain to me how to undo the blessing of the xom bootloader, if that makes sense at all, so the system startup process is once again normal?

The dual boot process went well just that when i decided to re-install OSX Tiger after re-partitioning the drive back to a single partition, i could no longer install the OS to the current partition. On the screen to select the drive to install the OS to, there's a red exclamation mark on the drive and a message saying that i cannot install the OS to the drive. I tried to repair permissions, but the problem still exists.

Now when i start the system i get a folder with a flashing question mark. I'm assuming that the system is still referencing the xom bootloaderfile, which is no longer there since i re-partitioned.

I did some research and i found that you can use a second Mac, boot the problem Mac up in Firewire Targert Disk Mode, and use the working system to bless the problem system to have it boot normally again. I'm not familiar however, with what bless commands to run to do so, if i'm on the right track at all.

The other option i was thinking off would be to set back up all partitions to the way they were when i dual booted, re-copy the xom bootloader file via Firewire Target Disk Mode, boot into Tiger, and reset to normal system boot before i changed it to use the xom bootloader. Again, i don't know what commands to run.

Can anyone help me if i'm making any sense at all.

This is very exciting despite my inexperience! Thanks very much in advance!

[thebalaa]

you have to start completely over. boot off restore cd,. repartion to 1 or 2 partitions depending on if you want to try again. you have to change the drive back to GUID.

[N3m35i5]

Thanks for the reply, but I have already tried that. Booted off the restore disk 1. The installer has a red exclamation mark over the newly partitioned drive and there's a message saying that the OS cannot be installed on the drive. I cannot continue with the OS install after this point. :(

[thebalaa]

you have to change the partition type to GUID i forget what button its under under disk utility. read more carefully

[N3m35i5]

Thanks! I'll give it a try.

[mrnippon]

There is no button to change the partition type in Disk Uititly - at least none that I could find. I had to erase the drive using the first tab in DU. Then I could install OSX. Hopes this helps.

[N3m35i5]

I think i found how to set it back to default boot.

Here's the line from the "howto.txt" instructions for the xom bootloader.
cd /System/Library/CoreServices
sudo bless --folder . --file xom.efi --setBoot

Here's what i found from this site (http://www.hmug.org/man/8/bless.php), which seems will revert me back to my original default boot running the cmds located below in bold. Damn, gotta wait till late Saturday to test. :(

FOLDER MODE
To bless a volume with only Mac OS X or Darwin, and create the BootX
file:
bless --folder "/Volumes/Mac OS X/System/Library/CoreServices"
--bootinfo "/Volumes/Mac OS X/usr/standalone/ppc/bootx.bootinfo"

MOUNT MODE
To set a volume containing either Mac OS 9 and Mac OS X to be the active
volume:
bless --mount "/Volumes/Mac OS" --setBoot

INFO MODE
To gather information about the currently selected volume (as determined
by Open Firmware), suitable for piping to a program capable of parsing
Property Lists:

bless --info --plist

[onirix1]

Not sure if this will help:

http://forum.onmac.net/showthread.php?t=160
It mentions "options" buttons in Disk Utility.

And I also saw something about this Options button confusion on Macosxhints. It is not obvious but I think it is there, the option to format as GUID.

[Steve1496]

Can anyone explain to me how to undo the blessing of the xom bootloader, if that makes sense at all, so the system startup process is once again normal?

The dual boot process went well just that when i decided to re-install OSX Tiger after re-partitioning the drive back to a single partition, i could no longer install the OS to the current partition. On the screen to select the drive to install the OS to, there's a red exclamation mark on the drive and a message saying that i cannot install the OS to the drive. I tried to repair permissions, but the problem still exists.

Now when i start the system i get a folder with a flashing question mark. I'm assuming that the system is still referencing the xom bootloaderfile, which is no longer there since i re-partitioned.

I did some research and i found that you can use a second Mac, boot the problem Mac up in Firewire Targert Disk Mode, and use the working system to bless the problem system to have it boot normally again. I'm not familiar however, with what bless commands to run to do so, if i'm on the right track at all.

The other option i was thinking off would be to set back up all partitions to the way they were when i dual booted, re-copy the xom bootloader file via Firewire Target Disk Mode, boot into Tiger, and reset to normal system boot before i changed it to use the xom bootloader. Again, i don't know what commands to run.

Can anyone help me if i'm making any sense at all.

This is very exciting despite my inexperience! Thanks very much in advance!

Ok, I'll try here..
-The flashing folder means it doesn't see any OS X system folder.
-Zeroing over the drive in Disk Utility in Mac OS X Installer should allow you to reinstall OS X.
-If you want to set it back to the factory boot way..do this in terminal:
cd /System/Library/CoreServices
sudo bless --folder . --file boot.efi --setBoot
But if that sudo bless doesn't work, try this:
sudo bless --folder /System/Library/CoreServices --bootinfo --bootefi

Hope that helps a little.
Steve

[N3m35i5]

Heh, you guys are the best! I'll try all the great suggestions, and will post which one worked for future reference.

Thanks All!

[N3m35i5]

Not sure if this will help:

http://forum.onmac.net/showthread.php?t=160
It mentions "options" buttons in Disk Utility.

And I also saw something about this Options button confusion on Macosxhints. It is not obvious but I think it is there, the option to format as GUID.

Here's the original article (http://db.tidbits.com/getbits.acgi?tbart=08405). Under the Disk Utility section it reads, "...a critical yet nondescript Options button was added to the Partition tab. This shy button appears only when you've selected an external drive. Clicking it reveals a sheet that enables you to select the partition scheme prior to partitioning the selected drive."

Thanks for the information. The article explains, under DU section, why everytime i erase/partition my drive on MacBook Pro i still cannot install the OS. Its due to the APM partitioning scheme being applied rather than the GPT partitioning scheme which is required to boot MacTels. Since the Options button only presents itself only when an external dive is selected, I'll boot into firewire disk mode and partition the drive for the GPT scheme that way. One more thing to try. Thanks again!

[smartin53]

OK nice and simple instructions. If you are trying to just set it back to the default mac bootup but aren't erasing windows then just boot into OSX, go to the Startup Disk utility, choose the OSX option, and reboot. OSX will come up normally.

If you are trying to undo everything and go back to JUST OSX then you'll need to restore the system of course. Now thanks to the GPT the mbr is all funky and won't let you install OSX no matter which way you partition the drive. All you have to do is pull up the disk utility and specificly select the drive (not the partitions) and then choose the erase option. That will clear the XOM stuff and make a nice fresh single partition/mbr that you can edit, format, repartition, etc and install OSX on.

[N3m35i5]

OK nice and simple instructions. If you are trying to just set it back to the default mac bootup but aren't erasing windows then just boot into OSX, go to the Startup Disk utility, choose the OSX option, and reboot. OSX will come up normally.

If you are trying to undo everything and go back to JUST OSX then you'll need to restore the system of course. Now thanks to the GPT the mbr is all funky and won't let you install OSX no matter which way you partition the drive. All you have to do is pull up the disk utility and specificly select the drive (not the partitions) and then choose the erase option. That will clear the XOM stuff and make a nice fresh single partition/mbr that you can edit, format, repartition, etc and install OSX on.

Great...Thanks!

[N3m35i5]

Thanks again for all the great suggestions. In the end I followed smartin's instructions, which was the easiest for an inexperienced Mac user as myself. My problem before when i partitioned the drive to revert back to installing regular OSX was that i was selecting the partition to erase rather than the actual drive. Heh, i thought for a second that i fubar'd my new MacBook Pro. :eek:

[smash0r]

I actually just went through this, slightly different circumstances, but same result. Repartitioning would not clear the red X. However, using the "erase" tab did the trick.

[sdavis]

i had a more complicated problem i think, but what i did was Zero out the disk and that fixed the problem... took about an hour on a 250GB drive, so not too bad... and probably not a bad idea to make sure that the drive is totally wiped...

good luck!