CentOS

Hi!

AFAIK, the gdm version changed from CentOS 5.x (ver. 2.16) to CentOS 6.x (ver 2.30), and the new one has less capabilities than the older one (limited themeability, many commands changed, etc.) so that's the reason. For a little more background, read this: http://bheekly.blogspot.com/2008/10/gdm-224-aka-smb-shoot-me-bloody.html

Regards.

Workaround:

1. Ctrl-Alt-F2 to get a virtual console login prompt.
2. Log in as root.
3. "telinit 3; telinit 5; exit"