I am still really confused.. HOW was this issue resolved? I have recently upgraded to multisite and am having the exact same problem as mentioned in the first post. My .htaccess file is exactly as posted by Jaap above. I can navigate the main blog fine, but attempting to access the backend or view a newly created site yields a 404 and Apache directory listing, respectively. I can’t help but think this is some simple permalink fix, but I’ve fooled around for hours and still no go. What information can I provide to have someone walk me though what to try? Using WP 3.0.1. Webpage: https://www.nauunderground.com