I tried to install Fedore Core 4 on my seagate external USB hard drive. I used my IBM Thinkpad T42 laptop with Win XP Professional to attempt this. Initially I ran into problems because my USB hard drive was not recognized and not listed as an option to install Linux. Then I ran Linux in expert mode which solved this problem. This time I was able to see the USB hard drive and successfully install Linux. I chose Grub as boot loader with Linux as default option if none was selected. When I restarted after installation, Linux just doesn't boot. The menu for choosing the OS wasn't even displayed and I got an OS not found message on the screen. Now I tried to boot linux with the Linux boot CD. Everything is fine and I get the boot prompt. Now if I press Enter, Linux should boot from the CD in graphics mode. But all I got was a blank screen. It just doesn't boot even from the boot disk. I tried the linux text, linux expert, linux rescue options at the boot prompt but all to no avail. I just get the blank screen all the time. So now I cannot boot Linux from the USB hard drive and also from boot CD. Please, some one guide me and help me with this. I just cannot figure out what must have happened after the Linux installation on the USB hard drive. Of course I was able to boot Win XP after I disconnected USB hard drive and restarted. But now even with USB hard drive disconnected I just couldn't boot Linux. Please help me!!!!