WordPress 406 errors “Not acceptable…”

If you’ve recently upgraded to WordPress 2.1, you may encounter a 406 error when you try to post, edit posts, access options, etc. This has something to do with your host using mod_security, or something. A good 45 minutes of searching did not turn up an exact reason for this.

But it did turn up a couple of workarounds. One involved turning the mod_security engine off completely, but that’s a bad idea because mod_security helps keep your files secure. Instead, you can turn it off just on those files that are acting up:

1. Create an .htaccess file in your /wp-admin folder.
2. Put the following in it:

<Files options.php>
SecFilterInheritance Off
</Files>

<Files post.php>
SecFilterInheritance Off
</Files>

<Files edit.php>
SecFilterInheritance Off
</Files>

<Files page.php>
SecFilterInheritance Off
</Files>

See how it works?  If you’re encountering the error when you try to “edit” files, you need to turn off security just on the wp-admin/edit.php file.  You can make more of these for other pages by simply putting the page name in place of “options.php” in the top example.