Ugh, Linux. Creating a new site results in "not found on this server"

I just set up multisite on my slowly-growing-more-hated Linux server. I turned off SELinux, so the incredibly annoying added security is off. First, before I go on, this is a Linux box in my house, only on my internal network, just for testing.

Okay, so I did the normal 3.0.x network setup. I created an .htaccess as stated in the instructions. All seemed good, so I created my first subdirectory site. WP said it created. But if I try to visit the backend or the site, I get this:

The requested URL /wp_aieditor/trackyourcandidate was not found on this server.

I wasn't sure about permissions, so I took a sledge hammer to the problem and made EVERYTHING in the WordPress directory, recursively, 777. It's still not working.

Any ideas?