Remove Featured image not working

Hi team,

I have currently an issue where the “remove featured image” is not working for me for all wordpress installation that I have on a specific VPS (Virtual Private Server)

I have copied the exact wordpress files and DB onto a different server (host) and the feature seams to work.

i have tried to use Firebug to try and see if any errors are thrown, I did not pick any. I can only pick a timeout issue of the admin-ajax.php

At the moment, I think that the issue is a server issue and I was wondering what are the features (requirements) or modules that need to be enabled on the server (e.g. CURL, GD, etc…) for this to work. I believe this is related to the ajax admin php file and the way it works, or I might be wrong.

I’ve also noticed that when updating plugins, the progress is not asynchronous, it actually updates everything and then the page refreshes.

Thanks in advance.