If possible, try to find out exactly what has happened. What were the exact commands you entered just before the error appeared for the first time? Were there other people with root access working on the system at that time? What were they doing? What exact commands were they using?
If there is a permission problem affecting the critical libraries and loader files, any non-root logins may fail. Don't log out of any shell sessions with root privileges, if you still have any sessions active. Until the problem is fixed, it may be impossible to log in normally.
If there are no working sessions left, try to login as root on the system console: this might work while other login methods fail.
If you can log in but have difficulties running the commands, try entering this command first:
export PATH=/sbin:$PATH
This makes the system use statically linked versions of basic commands, reducing the dependence on various libraries. These commands may lack some functionality of the full versions, but they have a better chance of working while this problem remains unfixed.
If you can access the system in any way, find the answers to Dennis's questions. They will give us more clues about the extent of the damage.
MK
MK
