I installed ubuntu 9.04 to my Maxtor external hdd. I have no internal hdd. I can boot
 

I installed ubuntu 9.04 to my Maxtor external hdd. I have no internal hdd. I can not boot from my external drive. It always says no OS unless I put the disk in the cd drive.I can not afford another internal hdd for awhile. The computer is a Dell 5100. I have a lot of experience with computers but I just do not understand. I have had a stroke so maybe my mind is still not working correctly
dont33

Being able to boot from an external usb drive depends on your bios. Older computers often don't have a bios option to boot from usb, in which case you are just out of luck. You could try updating your bios.

Even if your bios does support booting from usb, it may not automatically do so. You should look at the boot order to see if you can add usb device to the list.