Hi Thomas,
Its fairly simple, no re-installation required.
You just have to reboot your system.
You can find the solution easily with Google, I am just copy-pasting once such
way.
Press "e" on the GRUB screen where you select the Fedore you normally boot.
Select the line containing "kernel", and press "e" again. GRUB will display the
line in edit mode.
Add "single" to the end of the line, and press return. GRUB will return you to
the previous screen.
Press "b" to boot the system into what will now be single user mode. The
system will come part of the way up, and then drop you into a root shell - the
prompt will look like this:
sh-2.05# _
Now type "passwd" to change the root passwd and reboot the system.
--
Satish
