How to remove Query String "?" (question mark) from URL (Using Wordpress)

Do you have W3 Total Cache Installed ? (Wordpress Plugin) , If you do

Go to the Browser Cache Tab

Untick

Prevent caching of objects after settings change

Whenever settings are changed, a new query string will be generated and appended to objects allowing the new policy to be applied.

Clear the Cache then It's gone :) Hope this helps

-- Source Myself (Having the same issue myself )

Go to the Browser Cache Tab > untick "Prevent caching of objects after settings change".

This will slove the issue.

Change your Permalink settings from the default with question marks to a format you prefer under /wp-admin/options-permalink.php

• Default: http://www.example.com/?p=123
• Day and name: http://www.example.com/2012/03/02/sample-post/
• Month and name: http://www.example.com/2012/03/sample-post/
• Numeric: http://www.example.com/archives/123
• Post name: http://www.example.com/sample-post/
• Custom Structure: /%year%/%monthnum%/%postname%/

Add this code to your functions.php file, it works for my sites.

function _remove_script_version( $src ){
$parts = explode( '?ver', $src );
    return $parts[0];
}
 add_filter('script_loader_src','_remove_script_version', 15, 1 );
add_filter('style_loader_src','_remove_script_version', 15, 1 );