after a power failure I couldn't boot my computer normally.
after some time I could boot in interactive mode unchecking smartd option.there is something wrong with smartd.
I even had to remove emacs and some other program too.
when I try to open gedit or acrobate reader or any other program in terminal as root I get the following error:
Xlib: connection to ":0.0" refused by server
Xlib: No protocol specified
(gedit:4015): Gtk-WARNING **: cannot open display:

But I cam open gedit and other programs from menu.
I think I have lost some of my libraries too.
My home directory is alse became read only also.

I cannot configure SERVICES from menu where I need to enter my root password.

Speaking only for the Xlib message, it appears that the X server is not accepting connections from the local host, so it would seem that issuing 'xhost + localhost' should permit connections for gedit or Acrobat or other X applications.

The fact that this is happening after a power failure suggests that some filesystem corruption may have occurred. Have you run fsck on everything? Just a suggestion.

-Alan

I already installed a new fc4 in a new hard disk. but I use my old hard disk to store some unnecessary files. I cannot install any operating system on my old hard disk
thank you for help