Can't get UBCD to boot - checksum error

Try looking for help here if you are having problems with the latest beta of Ultimate Boot CD.

Moderators: Icecube, StopSpazzing

Post Reply
Message
Author
vizfxman
Posts: 4
Joined: Sat May 29, 2010 3:19 am

Can't get UBCD to boot - checksum error

#1 Post by vizfxman » Sat May 29, 2010 3:31 am

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.

Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

Re: Can't get UBCD to boot - checksum error

#2 Post by Icecube » Sat May 29, 2010 11:21 am

vizfxman wrote: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.
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:

Code: Select all

mkisofs -iso-level 4 -l -R -J -joliet-long -D -V "UBCD501" -o "../ubcd501-custum.iso" -b "boot/isolinux/isolinux.bin" -c "boot/isolinux/boot.catalog"  -hide "boot/isolinux/boot.catalog" -hide-joliet "boot/isolinux/boot.catalog" -no-emul-boot -boot-load-size 4 -boot-info-table .
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/

vizfxman
Posts: 4
Joined: Sat May 29, 2010 3:19 am

#3 Post by vizfxman » Sat May 29, 2010 6:34 pm

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.

Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

#4 Post by Icecube » Sun May 30, 2010 10:51 am

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

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:
The correct command to type (from windows cmd) is: ubcd2iso "%Homepath%\My Documents\ubcd-extract\" "%Homepath%\My Documents\customubcd.iso" (iso filename must be specified, unlike stated in the tutorial)
Download Ultimate Boot CD v5.0: http://www.ultimatebootcd.com/download.html
Use Parted Magic for handling all partitioning task: http://partedmagic.com/

vizfxman
Posts: 4
Joined: Sat May 29, 2010 3:19 am

#5 Post by vizfxman » Sun May 30, 2010 2:49 pm

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.

Icecube
Posts: 1278
Joined: Fri Jan 11, 2008 2:52 pm
Contact:

#6 Post by Icecube » Sun May 30, 2010 3:13 pm

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

vizfxman
Posts: 4
Joined: Sat May 29, 2010 3:19 am

#7 Post by vizfxman » Sun May 30, 2010 5:44 pm

Thank you Icecube!

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

oron
Posts: 1
Joined: Fri Feb 17, 2012 8:43 pm

Re: Can't get UBCD to boot - checksum error

#8 Post by oron » Fri Feb 17, 2012 8:46 pm

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

The Piney
Posts: 370
Joined: Mon Apr 30, 2007 11:06 am
Location: FL

Re: Can't get UBCD to boot - checksum error

#9 Post by The Piney » Sat Feb 18, 2012 1:52 pm

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

http://hints.macworld.com/article.php?s ... 0083853834

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.

Post Reply