[support] Help with moved site.. Access denied.

Hi All, I am pulling my hair out here trying to move a Drupal site from a cpanel based web host to a Virtual private server running Ubuntu 10.04.. I have moved the files and database and updated the settings file but when trying to load the site in get a completely blank white page with the words "Access denied." at the top.. Other than that there appear to be no errors being logged anywhere.. I have made absolutely sure the database credentials are correct.. Anyone have any pointers? Thanks..