I tried to change the mount points in Fedora 10 by rebooting my computer into one of the three other Linux distros I have on my computer, SUSE so I can open Fedora's /etc/fstab. When I reboot back into Fedora, it does not mount those partitions at all. I tried changing /etc/fstab back but the same thing happened again. When I plug in my external hard drive, it says "Failed to mount partition" then when I click "Details" it says "Cannot Read fstab". In SELinux, it says something similar. I have installed. I did the same in Ubuntu, but when I changes fstab back, it worked fine. I used gedit to modify fstab.

Post the original and edited fstab.

Run '/sbin/fdisk -l' as root to see what devices you have and compare the devices with your fstab.
Are you sure that you have not corrupted your partition table with some reckless command?

Debian