Page editor redirects to log-in

Hi I recently completed a site on localhost for a client and uploaded it to the Host. I followed my usual path of installing a fresh version of WordPress on the server, and editing the information so I can just replace the body of the database and replace the files and that usually works fine. The site works great but when I’m in the backend and click on “All Pages” i’m redirected to a page that says I have already installed wordpress, Log In. If I’m logged in and on the site, i can click edit page and theres no problem, the add page button works fine too. But The “all pages” tab will not work at all, the database shows as OK when I run a check and the information in WP-Config.php is fine too.

What have I missed?