Enable GUI Root login in Fedora13,RHEL6..etc
Step 1 :-Login as a root from your terminal
[itsolutions@svk]$ su – root
Password:-
Step 2:- Now go to your /etc/pam.d/ directory.
[root@svk]# cd /etc/pam.d/
Step 3:- Edit the gdm file (Find and Comment or remove below mentioned line into your gdm file )
[root@svk pam.d]# vi gdm
#auth required pam_succeed_if.so user != root quiet
Save & Exit From that File. ( In Fedora10 Till step 4 is enought to Login as a root from GUI but for Fedora 13 you need one more file to edit otherwise you cannot Login as a root even though you edited gdm file).
Step 4:- Here is the additional file that you need to edit and that file name is gdm-password. Open gdm-password file editor. (Find and Comment or remove below mentioned line from gdm-password file )
[root@svk pam.d]#vi gdm-password
#auth required pam_succeed_if.so user != root quiet
Step 5:- Save & Exit from File. Now Logout and Try to Login as a root user. Now you are able to Login as a root user from GUI