Greetings all,

I'm sure this is a noob question, but after scouring the internet for answers and coming up empty, I'm frustrated and desperate.

I have a Mac Pro and am running Snow Leopard and Windows 7 Pro (64-bit). I'm attempting to flash a new graphics card, and so I have to be able to boot up the UBCD to a prompt. I've burned five CD's now and each and every one gives me the same message:

"ISOLINUX 3.86 2010-04-01 ETCDisolinux: Image checksum error, sorry...
Boot failed: press a key to retry..."

I'm not sure what I'm doing wrong. I downloaded ubcd501.iso and am burning that to CD using MagicISO. I've tried burning at the slowest speed and at mode 1 and mode 2.

I also downloaded md5sum and verified that everything matched, and it does.

I should also note that I'm trying to add a few files in a folder called "Mac" to the iso (in MagicIso) before burning.

Any help is greatly appreciated.

This is the problem.
NEVER use an ISO editor for bootable CDs. Always create the iso again with mkisofs. You get the checksum error because the isolinux.bin (boot loader) file needs to be patched, so it knows its location on the ISO. This patching is done by adding the "-boot-info-table" parameter to mkisofs.

Extract the UBCD501.iso to a dir named ubcd-extracted.
Add your Mac folder in the ubcd-extracted dir.
Open a command prompt and cd to ubcd-extracted.
Run the following to generate the iso:

You can also test the ISO first in a virtual machine like VirtualBox, to see if the ISO boots.

_________________
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

Hi Icecube,

Thank you so much for your reply.

I sort of makes sense to me that the way I was doing the boot disc wasn't working...

So I downloaded mkisofs and can't seem to use it. I'm not sure where it goes so I put it in the ubcd-extracted directory. Then it was saying I needed cygwin1.dll, which I downloaded and put in that same directory. Now when I'm in the shell and type mkisofs I get a message saying "The procedure entry point__ctype_ptr__ could not be located in the dynamic link library cygwin1.dll.

This is all just above my head.

I was assuming that you where trying to build the iso with Snow Leopard .

UBCD has already a mkisofs executable.
Instructions for building the iso on Windows:
http://wiki.ultimatebootcd.com/index.ph ... ng_the_ISO
There is only a slight error atm, below is the correct version:

_________________
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

You were assuming along the correct lines, Icecube. I'm the numbskull who doesn't know what he's doing and was booting into Windows.

I'll give it a try in Windows following the instructions in the link you provided.

I'll look online, but what's the best way to extract the .iso to a folder named "ubcd-extracted" in Windows 7?

Thanks for all of your help.

Try 7-zip.

_________________
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

Thank you Icecube!

That worked great. I've spent the last four days trying to figure this (what should be a simple process) out.

Can you please explain me how to run the mkisofs on my mac ?

I've never used mkisofs on a MAC but here are some links from a quick Google search.

http://hints.macworld.com/article.php?story=20020520083853834

Here is a mkisofs gui tool for MACs -> http://www.ugsoft.de/intl/mkisofstool/index2.html

Info -> http://linux.about.com/library/cmd/blcmdl8_mkisofs.htm

There are many other links/sites.