Burning MSDN iso's using Disk Utility "Could Not Validate Source - error 254"

Here's the forum post that led to the solution.

http://hintsforums.macworld.com/showpost.php?s=ab4d0a1c1c611632ea4f08bfe854927a&p=565229&postcount=3

To be fair Disk Utility is a Mac only program and as such is limited to being a Mac only tool....not really for use trying to do this funky stuff ;-) 

What you are trying to do is clone a UNIX install iso to a USB stick that is formatted incorrectly for your purpose...not the best start.

Firstly you need to format the USB stick to MS-DOS FAT32 with Master Boot Record Partition. You can do this in disk utility.

Next you need a clone tool....as i think most of the in built tools (ASR) may not work with FAT32 maybe try using http://www.twocanoes.com/winclone/ it may work.

Superduper may work and maybe you can try using ditto from terminal to copy the files from ISO image to USB stick.

sudo ditto /Volumes/NAME_OF_MOUNTED_ISO /Volumes/NAME_OF_USB_KEY 

or 

sudo cp -r /Volumes/NAME_OF_MOUNTED_ISO /Volumes/NAME_OF_USB_KEYor 

RSYNC it not sure if that will work either !

to manually copy all the files (including hidden ones)

ditto is what worked for me.