This is for those of you hunting for the Cheatin’ uh? WordPress error when developing custom post types.

It’s most likely an issue with what you named a custom taxonomy that you intend to attach to a custom post type.

In our case we had…

register_taxonomy("Types", array("portfolio"), array("hierarchical" => true, "label" =>; "Types", "singular_label" => "Type", "rewrite" =&> true));

This is a frustrating error because you simply get the “Cheatin uh?” message.

Here’s the fix

register_taxonomy("types", array("portfolio"), array("hierarchical" => true, "label" => "Types", "singular_label" => "Type", "rewrite" => true));

Notice the difference? The fix is your custom taxonomy’s name has to be lower case. That should save you a couple hour hunt down a rabbit hole.