If you are using grub2 ( arch linux or ubuntu 9.10 karmic koala ) you might notice some problems after kernel updates.
Symptoms – System won’t boot and you will get error similar to this:
Error – you need to load the linux kernel first.
Quick solution would be to boot from Arch / Ubuntu CD and go to recovery, mount your boot partition and get root shell ( You usually got all this in Ubuntu recovery menus, in Arch you might wanna use the shell 😉 . Go to /boot/grub and edit device.map ( what probably went wrong is that your hdd definition changed in this file and its currently trying to boot from wrong drive ). In my case changing /dev/sda to /dev/sdb solved the problem. Do not forget to run
update-grub2 to re create grub.cfg and reboot. Your system should boot as usual 🙂