Update
Works with Fedora 17, change required in only below file.
/etc/pam.d/gdm-password
Below Works with Fedora 16
Root Login on Fedora is not as easy as Ubuntu Root Login, here you need to modify two files to get root access.
You need to modify content of following files
/etc/pam.d/gdm
/etc/pam.d/gdm-password
You’ll find pam_succeed_if.so user != root quiet in above files, replace root with anything e.g test
I replaced root with test & was able to login to system using root.
OR Comment the entire line.
Or You may choose to remove “user != root” from line, rather above two options as suggested by Manuel (Comment Section)
We do not encourage readers to login as root, login with non-root user will keep your linux secure.
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