There isn't the library enet.

However your codeblock version is really old. You should download a nightly build. There is a nightly build of 21 July 2009, instead your version is of 28 february 2008...
I think also your MinGW is old, there is gcc-4.4 now, you should use this

Which version of codeblocks and mingw are you using?
The latest stable version of codeblocks is of the 28 Feb 2008, so it's obsolete.
You should download one of the nightly builds, but they, as nightly builds, aren't really stable.