Suggest:
Boot with an install CD/DVD in rescue mode.
Mount your file system (this should happen automagically)
edit /mnt/sysimage/etc/inittab
Set your default runlevel to 3 (currently it is set to 5)
quit the rescue, and reboot your hard drive.
 
Now you will have the shell available to debug what goes wrong when you command 'startx'

From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of Chaitanya Yanamadala
Sent: Wednesday, May 12, 2010 10:21 AM
To: CentOS mailing list
Subject: [CentOS] your session only lasted less than 10 seconds error

hai i have run the halt command from the xshell and the machine got restarted, now when i restart the machine, i am getting this error . I have tried to press the CTRL+ALT+F2 and tried to login with the root user but that one is also not working.
can any one help me with this..
this the error message i am getting after i tried to login

" your session only lasted less than 10 seconds ...try logging in with one of the failsafe sessions to see if you can fix the problem"
and it published details
(.xsession-errors file)
/etc/gdm/PreSession/Default: Registering your session with utmp
/etc/gdm/PreSession/Default: running: /usr/bin/sessreg -a -u /var/run/utmp -x "/var/gdm/ :0.Xservers" -h " " -l ":0" "chaitu"
session_child_run: Could not exec /etc/X11/xinit/Xsession default

Regards
Chaitanya

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