Nessus is security and network related program so I decide to put my question here........ HOW CAN I INTALL IT!!!!!!????
There's your first problem, wrong diagnosis. You have probs installing the app, and not security related issues with the app or functionality: so it should be in either /general, or /software.
And it says can't find some library,
What library? Why not show some errors?
and: "Make sure your library loader is configured properly and that nessusd is in your $PATH.." I can start nessus, but I am wondering what that expression above means?
execute this: "ldconfig -p -v" and see if the library you installed is mentioned there, else you will I. have to add the path where you installed the library in /etc/ld.so.conf or II. if the path is there, update the cache running ldconfig.
Now execute "echo $PATH" and see if nessusd is installed in one of the dirs mentioned there, if not, move it there.
//Mod.note: moving to software.