Error regarding Combinatorca

Hello…
I’m new to Mathematica and just started to work with the trial version of Mathematica. I get an error like “Get::noopen: Cannot open DiscreteMath`Combinatorica`. >>”
when I’m including << DiscreteMath`Combinatorica` …what is the problem can anyone tell…

<< Combinatorica`

All the functionality in DiscreteMath`Combinatorica` is available in the newly created Combinatorica Package.

this also gives error like…General::compat: Combinatorica Graph and Permutations functionality has been superseded by preloaded functionality. The package now being loaded may conflict with this. Please see the Compatibility Guide for details.
Message::name: Message name 4::usage is not of the form symbol::name or symbol::name::language. >>

what to do??

I think that is a warning, rather than an error message. You should still be able to use functions in the Combinatorica package.

Combinatorica is “obsoleted” since version 8 of Mathematica and there are several symbol names that conflict with built-ins. However, Combinaotrica still contains many useful functions that are not available elsewhere. Because of the name conflicts, after loading Combinatorica you need to explicitly specify whether you’re referring to a built-in symbol or a Combinatorica symbol, e.g. System`Graph or Combinatorica`Graph

Many find ti convenient to load Combinatorica as

Block[{$ContextPath}, Needs["Combinatorica`"]]

This won’t add the package to the context path, so there won’t be name conflicts. But now you need to explicitly use the context of every Combinatorica symbol (i.e. write Combinatorica`Automorphisms instead og Automorphisms), not just conficting ones such as Graph.