Page Not Found (404)

Are you using HostGator?

YEs.

Make a copy of wp-comments-post.php and name it blahblah.php. Then, when calling the comment form in your theme, make it use the new file like this:

comment_form(array('action' => '/blahblah.php'));

Or, use a different web host ??

I am having this same problem, but am using BlueHost. How do I fix it?