WordPress MU

I just installed Wordpress MU locally and I seem to be having a problem. Everything I click on give me 'Error 404 - Not Found' including archives, categories, blog posts, etc. Everything with the exception of pages. I only have this problem with my main blog. When I create a new blog, it works fine.

Any ideas?

Thanks guys.

I figured it out. It had to do with the permalink structure. For some reason my installation came with a custom permalink setting that looked like this /blog/%year%/%monthnum%/%day%/%postname%/

That's what lead to the 404 error

What version of MU? The sidebar says 2.7.1.

And by locally, what kind of computer? We have Macs, linux and the occasional Windows user. ;D