2.7.1 upgrade, content transfer problems

I have upgraded my wordpress to 2.7.1 and all of my content transferred over onto my dashboard. The content is also on the site, but whenever I click on a link or to see the rest of the content expanded it gives a 404 error:

Not Found
The requested URL /2009/lets-face-it-online-poker/ was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

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Apache/2.2.11 (Unix) mod_ssl/2.2.11 OpenSSL/0.9.8i DAV/2 mod_auth_passthrough/2.1 mod_bwlimited/1.4 FrontPage/5.0.2.2635 Server at criticalspeech.com Port 80

What have I done wrong? Its not my theme because I have tried different themes and had the same problem. All links pull the 404.