We found out what the problem was. It had nothing to do with the SEO module. The problem was that override was set to none so the .htaccess file was not even being used. Once we allowed override, everything started working fine.

I set up the module just fine in my dev site running on MAMP on my Mac. When I copied everything up to the Rackspace server and ran the install and set it to the same settings, it looks like it should be running, but when I turn it on, all the rewritten URLs return 404 errors. I created the .htacces...