How to Fix ‘Error 406′ or ‘Not Acceptable’ issue

Apache Mod Security update

last updated: march 2, 2014

Few weeks ago I started having “Not Acceptable! Error 406” on one of my WordPress sites when trying to save a post or a page. I kept getting the following message when trying to save a post.

Not Acceptable
An appropriate representation of the requested resource /wp-admin/post.php could not be found on this server

I tried many fixes and nothing seemed to have helped getting rid of the issue. So I decided to reinstall WordPress (How to Uninstall and Reinstall WordPress). Even the reinstall didn’t help! Later I found out that the “Not acceptable! Error 406″ occurs due to Mod Security updates on the server. So if you are having a similar problem then you can try one of the following methods to fix it.

Solution 1 for Fixing 406 Error

Backup your .htaccess file if you have one in the ‘wp-admin’ directory. Then make a ‘.htaccess’ file with the following content and upload it to ‘wp-admin’ directory.

<IfModule mod_security.c>
SecFilterEngine Off
SecFilterScanPOST Off
</IfModule>

You can use any text editor such as Notepad to create this file.

You will need to upload this .htaccedss file to your server. So if you don’t know how to upload a file to your server then check this tutorial on FTP.

Solution 2 for Fixing 406 Error

This is the solution that worked for me for my WordPress site.

Backup your .htaccess file if you have one in the public_html directory.

Open the .htaccess file with any text editor and observe the lines between the “# BEGIN WordPress” and “# END WordPress” tags. Make sure the lines look somewhat like the following. If not then update the file with the following content and upload it to the ‘public_html’ directory.

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress

Hopefully one of these solutions help fix your “Not Acceptable” error. Good luck.