ok im no computer genuis and just taught to give ubuntu 8.04 a try for the first time.

I have installed ubuntu on a 400GB external with no partitions on it. When i restart the PC the following message comes up:

Reboot and Select proper boot device or insert Boot media unselected BOot device and press a key

i have enter the bio disabled the pc's hard disk and set the external as the primary however still no change. Doesanybody know the problem??

The other much more worrying problem is that when i disconnect the external hardisk to run windows again and set my other hard disk as primary and disable the external i have the following error:

Grub loading stage 1.5

Grub loading, please wait...
Error 21

Can anyone tell me how to solve the problem please thanks alot

If you plug the external drive in, then set bios to boot first from the internal drive, linux will boot. This is not the behavior you want. You will get it because you installed the bootloader (GRUB) to the MBR of the internal drive.

You need to install GRUB to the MBR of the external drive, and restore Netloader (or whatever your windows is using) to the MBR of the internal drive.

This way, you can set the boot order to external then internal. When the external is plugged in, linux boots. When it is not, windows boots.

ok thanks for your help however unlike you im no guru in this. can you please give me a link to a tutorial or something or explain in easy english. sory for the hassel but im really ont used to ubuntu

http://www.linuxquestions.org/questi...rddisk-640727/
Also GIYF:

http://ubuntuforums.org/showthread.php?t=224351
http://www.webtree.ca/windowsxp/repair_xp.htm