Comment 5 for bug 325786

"have you got any idea, if I could fix the crippled USB sticks created on Win XP a posteriori by running some magic isolinux commands from a Live CD environment?"

You didn't mention the type of Live CD, I'm assuming Ubuntu for the time being.

sudo apt-get install syslinux
sudo syslinux /dev/sdb1

(assuming /dev/sdb1 is the USB drive's FAT32 partition, you should be able to determine that from your partitioning tool when you formatted the disk)