restoring EFI partition

[typhoonman]

Hi, i have an hackintosh on a p5k installed using retail 10.5.6 + cdboot 132 + uinstalllerx86.

I do not use any bootloader, i choose operating system switching HD priority in P5K bios

 

I was inside OSX, i have resized the main OSX partition to 100Gb, leaving the other 400Gb unused

 

then i've rebooted on OSX to see if was still working.

 

then i've rebooted in Vista and formatted the blank space to an NTFS partition using Vista utility

 

Now i'm not able to boot on OSX anymore, i get boot error

 

I've tried also with cdboot132 but when i select that disk it gives me an error aswell:

[lotofnumbers] error sector 64, or something like that

 

Is there a way to restore OSX boot without erasing all the HD and reinstalling everything?

I have an EFI partition of 200MB at the beginning of the disk, i think it's the boot partition right? how can i fix that, can i delete that also? in Vista i'm unable to delete it, if i delete it am i able to boot osx using cdboot and then restore the efi partition using uinstallerx86 ??

 

thanks for any help

[srs5694]

First, despite what you may think, you are (or at least were) using a boot loader. Two of them, in fact: one for Windows and another for OS X. They might not have presented you with any menus, but they did exist. Boot loaders are 100% necessary to boot any OS. I'm not trying to nit-pick here; this is important because I suspect that what's happened is that your adjusting the partition size and/or creating a new Windows partition has damaged or destroyed your OSx86 boot loader.

 

The EFI System partition is required by true EFI firmware to boot a disk; it's used by EFI to store EFI-level drivers and other software. Some OSx86 boot loaders use this partition to store part of their code. It's not really a "boot partition" per se, though, at least not the way I think of that term -- your boot partitions are those on which actual OSes reside and from which they boot, and that doesn't describe the EFI System partition.

 

Now, to practical matters: Your best bet is to download the latest versions of two or three OSx86 boot loaders (PC-EFI, Chameleon, Boot Think, etc.), put their installers on a USB flash disk or a spare partition, and then boot your OSx86 installer. You can then use its Terminal program to get a command line and install one of the boot loaders. (Pick one at random, or based on perceived ease of installation based on its instructions.) Then shut down and see if it works. If it doesn't, repeat the process with the other boot loader(s) until you find one that works for you.

 

Note that there's some risk to this. You might end up rendering Windows unbootable, or you could damage your OS X installation. You can unplug the Windows hard disk to minimize the risk to it, if you like.

 

Good luck.