[CentOS] Can't login after installing Centos 5.5

Sat Oct 2 18:14:25 UTC 2010
Phil Schaffner <P.R.Schaffner at IEEE.org>

On Sat, 2010-10-02 at 17:55 +0100, Peter Crighton wrote:
> At no point can I get to a text login screen (Ctrl-Alt-F1) so I can't
> even debug it!
> Can anyone suggest what is wrong or how to overcome it?

Boot in verbose mode to runlevel 3 by hitting a character at the start
of the boot to get a GRUB menu (<space> in convenient).  When the menu
appears type "a" to append (no quotes - actually edit) the kernel line.
Backspace through "rhgb quite" and add "3" then <Enter>.  Should boot to
a text console where you can debug.  If that fails, then try single user
mode - just substitute "1" for "3".