Pages/Posts Not Publishing

Reoccurring problem across multiple new wordpress installs; tried to publish a post to http://buddhatunes.com/50, or page to http://icecast.fm/chill, or http://buddha.fm/activity -- and all come up with 404 errors.

I have tried changing the 755 and 644 permissions but no success. Originally, thought this was a one website/buddypress problem, but it seems to be more of a wordpress set up issue across multiple websites.