for some reason, it seems my install / mbr / darwin bootloader has corrupted. the system boots up flawlessly with the cd in drive. i rummaged through the forums and found only this fix:

i did this and nothing changed - still got stopped with the "boot0: MBR / boot0: error" message.

i've attached the list of my drives as shown in the disk utility. i boot off of "the big lebowski". all partitions and external drives are Mac OS Extended (Journaled). i'm running ideneb 1.3 / leopard 10.5.5 and there are no other issues once booted up.

i should note - i just checked into the 'startup' disk options and my OS X install doesn't appear under the options. the install cd and Network Startup do, but not any of my hard drives.

what gives?

Same thing here. I'm using iDeneb 10.5.5. I just installed and everything is working besides this. I tryed to use the OSX86 tools that came with the install and clicked "Install EFI/Run FDISK". PC_EFI v8 won't install because it says "DD unable to be completed." Next I tried the Chameleon EFI. This one installs, but gets the same error you are. Finally I try No EFI (Darwin Bootloader) and it says "DD unable to be completed". So the only one i'm getting to install is Chameleon EFI but it's still saying the same error.

Use Darwin boot loader from OSx86 Tools. But did you try this first:

1. boot with -s option.
2. fdisk -e /dev/rdisk0
3. flag <partition no. where OSX is installed>
4. write
5. update
6. quit
7. reboot.

Do you mean to boot the DVD with the -s option and open the terminal? Because you can't boot into the hard drive with different options.

Ok, I booted with the DVD and did what you suggested. The No EFI option in the OSX Tools still says DD was unable to complete.

Ok, I think i've figured out why you're steps aren't working. I have a SATA disk and according to OS X it's installed on partition 5. When i type print when the /dev/rdisk i get a NTFS partitoin and a DOS partition which the NTFS is my vista.

Found out my SATA drive's address is /dev/disk0. OS X says it is installed on partition 5 but when i try to flag partition 5 it says there is no partition 5.

macnutty, thanks for your help thus far.
same here. i tried all variants of the solutions considering this, including /rev/disk0s5, but nothing worked out. interestingly, flagging partition 2 changed the boot error from "boot0:mbr / boot0: error" to "boot0: mbr / boot0 : done".

so i do think i need to reinstall darwin, if possible. could you add some specifics on installing it? from osx86tools, is it through the "Install EFI / Run FDISK" option? in that, i have the option of installing to either of my partitions - should i install to both, just in case? and should i stick with darwin, or use a different EFI (it offers PC_EFIv8 and ChameleonEFI, though i should note i have zero hardware issues/needs right now)

Same happens with me. I've looked around and it seems if you want least problems and want to be able to dual boot (like I am) you want to use the No EFI (Darwin) bootloader still, so you can choose Windows on boot if needed. I too have no hardware problems left, besides this. I think the problem is that we can't flag the OS X partition for boot using fdisk, and that's what's causing the OSx86 Tools to fail at installing the bootloader. I'm going to attempt to use another program to flag the partition, maybe my GPARTED CD or a Windows installation disk might do it. I'll try a few things and let you know back.

So I used my GPARTED disc and marked it active and it didn't work. I'm gonna try it again but this time then do the OSx86 tools and hopefully it will install.
Friend's playing Crysis Warhead at the moment on Windows so i'll have to wait to try it out.

i tried the same EFI installations and got the same anticlimactic result, for both of my partitions. i should add that i am not trying to dualboot - i have drive partitioned for security/space management reasons.

i have a feeling this will end in me having to format the drive yet again and try another fresh install of leopard, but it being such a minor issue, was hoping the fix would be clear and easy. anyone reading this, please post if you have gone through similar problems or have any suggestions.

Yes that is what i ended up doing. What you have to make sure is the partition that OSX installs on is a PRIMARY partition. Mine was extended and this is what was causing the problem. So go grab the Gparted Live CD and boot it up. Delete your current OS X partition. Then make a new one, go ahead and make it HFS+, you'll have to erase it later though. Then go and restart the OS X install disc. Go to the Disk Utility and find the drive (mine was disk0s2) and then tell it to erase that one with the file format of your choice, and there you go! Install as normal(though I did choose under kernel the 9.4 one maybe that made a difference as well). Then remove your install disc upon start up and there you go! At least, that is what worked for me. Everything works out of box! YAY

For me this seems one of the major problem in the OSx86 world
..unbootable disks , wrong and faulty bootloaders , MBR errors , GUID errors , not functional backups and clones...brrrr

i have been in that hell 3 months now ...call me an idiot ....
I definitely find OSX86 tools a step in the right direction , but for me it worked once , next time it didn´t work at all

I wonder why there is not one effective solution where our geniusses get together and find something really working
for not so enlightened people like me..

For my part I think about buying an EFIX and put an end to this everlasting trouble.

Best
m