[ubuntu] pendrive usb-stick with grub2 not booting partitions on harddrive

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http://ubuntuforums.org – I have a Grub2 multiboot laptop with Ubuntu 10.10 in /dev/sda6 ; Ubuntu 9.04 in /dev/sda7 and WindowsXP in /dev/sda1 , both Ubuntu's and XP are booting fine. I recently made a Grub2 multiboot usb-stick using the cookbook from pendrivelinux.com "Boot Multiple ISO from USB via Grub2 using Linux" It works fine and I can boot several iso's that I placed on the usb. I then tried to expand the grub.cfg on the usb-stick in order to boot the XP and Ubuntu on my laptop harddisk I copied menuentries from the grub.cfg on my laptop and placed them in the grub.cfg on my usb-stick. When I boot t (Hardware)