WP E-Commerce breaks Media Library

Hello,
I am using WP e-commerce 3.8.8.5 and I am having troubles with the media library. The problem appears when I try to add an image to a post. I click on the button to add an image and the media library shows up but it is empty. It shows absolutely nothing, although I have more than 70 images stored.
As suggested in other posts related to similar problems, I deactivated all plugins in order to check which one was causing the problem. When all plugins were deactivated the media library worked fine, then I activated them one-by-one and the problem appeared again when activating WP e-commerce.
Does anyone know how to fix it? I have also tried with Hotfix but still, it does not work.
Thanks,