WP Minify should work out of the box for many people. For the rest of you, who tinker and venturing into advanced options and experimenting, you’ll probably run into issues causing your minify calls to return “400 Bad Request” code. Here’s a quick troubleshooting guide on how to debug this error message quickly and efficiently.
- Enable “Show minify errors through FirePHP” in WP Minify settings.
- Enable Firebug
- Enable FirePHP
- Load the page that has the broken minify call.
- Expand the broken minify call and then view error message.
- Exclude this file in WP Minify options.
Check out the plugin forum to see if others have ran into and solved the same problem you are having.