Desktop Does Not Start Up

[stan]

On Sun, 14 Feb 2016 22:23:27 +0000
Richard Ibbotson <richard.ibbotson at gmail.com> wrote:

> Hi
> 
> I did a dnf update on my F23 workstation. After rebooting to make
> sure that  the updates were working properly I find that I can't get
> to the login screen.  I see the blue Fedora logo for a split second.
> Then the command line appears with a message to do Ctrl-D or login as
> root. Nouveau drivers for the graphics card.  I can login as root and
> use a text editor.  After the failed X startup  I can  see the
> following error message on the screen
> 
> Error getting authority: Error initialization authority: Could not 
> connect: No such file or directory (g-io-error-quark, 1)
> 
> If I have a look at the log in /home/user/.local/share/xorg it says...
> 
> Fatal server error: xf86OpenConsole: Cannot open virtual console 1 
> (Permission 
> denied.
> 
> If I try startx as as a user or as root I can see.. for example... in 
> /var/log/Xorg.0.log...
> 
> dbus core: error connecting to system bus: 
> org.freedesktop.Dbus.Error.FileNotFound (Failed to connect to socket 
> /run/dbus/system_bus_socket: No such file or directory)
> 
> Can anyone suggest how to fix this ? I can't send in lengthy logs due 
> to the fact that I can't ssh into the machine or run a second or
> third console. Access to one console only. 

What does journalctl -r show happening before the error?

Is there a pid file left around from a previous crash?

What updates were performed?  I think you can see that
in /var/log/dnf.log?  If there is something there that looks like it
might have caused the problem, you can do a dnf downgrade on that
package, or if it is no longer available in older version go to 
http://koji.fedoraproject.org/koji/search?match=glob&type=package
to pick up the older binary rpm and use
dnf -C downgrade [package name].