ONLY USE ROOT ACCOUNT IF ITS A MUST TRY AND USE REGULAR ACCOUNT AS MUCH AS POSSIBLE (YOU COULD BREAK YOUR INSTALL USING ROOT ACCOUNT IF YOU DO SOMETHING WRONG) FOLLOW THIS GUIDE EXACTLY!
ok, first open a terminal and type su then your root password that you created when installing your debian 7 wheezy os.
type: apt-get install leafpad (this will install leafpad text editor which is what we are going to use next) once installed stay in root terminal.
type leafpad /etc/gdm3/daemon.conf under security type this (AllowRoot=true) no brackets so it should look like this:
[security]
AllowRoot=true
(once it looks like this go to file then save then you can exit the window)
type leafpad /etc/pam.d/gdm3 and press enter you will get a window open that contains this text:
#PAM-1.0
auth requisite pam_nologin.so
auth required pam_env.so readenv=1
auth required pam_env.so readenv=1 envfile=/etc/default/locale
#auth required pam_succeed_if.so user != root quiet_success
@include common-auth
auth optional pam_gnome_keyring.so
@include common-account
session required pam_limits.so
@include common-session
session optional pam_gnome_keyring.so auto_start
@include common-password
comment out this line: #auth required pam_succeed_if.so user != root quiet_success
go to file hit save then exit window
now you can exit the terminal window aswell
now you can either logout or restart computer (restart would maybe be better just to make sure)
at login screen make sure (system default is selected this will be gd3 which you edited earlier)
just type username: root
then type your root password that you created during install.
hopefully this helps someone