I have a 320gb USB hard drive, one partition for my files, one for playing Wii games, and one which I would like to use for an Ubuntu instillation.

To do this, I partitioned my disk accordingly using Windows, then booted from the Ubuntu CD to install the OS to my external hard drive partition. It asked me where I wanted to install the boot loader, so I selected the hard drive itself, rather than the specific partition, reasoning that it would scan the hard drive for a boot record.

However, when I booted it (with USB boot selected) it simply said "No Operating System found, replace system disk and press enter" or something similar.

Where have I gone wrong with getting this to work?

Thanks in advance,
Laurence

Could you tell us which version of ubuntu you are using. You need to install grub to your external hd then leave usb as your first boot and it will work plugged or unplugged. You will have to restore your mbr on the internal hd.

Well, I'm using Ubuntu 10.10 (32 bit), and I assumed it would install grub automatically, when it asked me where I wanted the boot loader installed??

I am currently in the process of reinstalling ubuntu, having rearranged the disk so the ubuntu partition is at the beginning.

Thanks for your help so far, and I'll tell you how it goes after instillation's finished

Ok, I've finally managed to get it sorted . Turns out it was not as complex as iI though, simply that my BIOS was unable to boot from a USB hard drive. What confused me was that it's perfectly capapble of booting from a USB flash drive, and I though the BIOS saw them as the same thing.