host might wp-config.php problem

 define('CONCATENATE_SCRIPTS', false );

hi,

I have confirmed that it is an issue with Wordpress and not the server. Going to Wordpress's forums I found a fix for the issue you were having.

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Adding the following line in wp-config.php fixes the add media page.

define('CONCATENATE_SCRIPTS', false );
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Please provide me your domain name i will update.
You will need to add the line I mentioned before to all affected domains or contact Wordpress for further assistance.