i had the same (or a similar) problem. this is what i did to solve it:
by the way, the problem w/ mine was permissions...
folow linuxluser's directions on this link:
then i had to go to my home folder and...
find / -iname firefox
this resulted in:
note that if you want to run firefox from the command prompt, you need to have an entry in /usr/bin/ . /usr/lib/mozilla-firefox/ is the directory i installed to. /home/username/.mozilla/ is a hidden directory that firefox uses... it has profile information and whatnot.
i then had to use this command from my home directory:
chown <username goes here> .mozilla
(or from anywhere, you can type chown /home/<username>/.mozilla )
i also had to do the same for any directories inside this directory
um, i hope this helps... i'm new to linux too, so... pls correct any of my mistakes.