Error 404 – Not Found

Hi All
I’m new to WordPress, and startet last week to use it. I’ve created a blog on localhost (by using Wamp), i’ve used the multisite function and followed step by step to set it up.
But when i create a new site (by directory), and visit it i get error 404 – Not Found.

I’ve researched all over the net to find a solution but nothing worked. It’s proberly just me who’s studpid but i could realy use some help. I’ve spent 3 days trying to figure it out and im goint nuts!

Hope someone have a solution.

Ps: Sorry for my bad English