Thank you! The conflict test helped. The problem was in UsersWP plugin. After deactivating it everything works fine. The weird thing is that this plugin is recommended by GD, and sooner or later I’ll need it. So it would be nice to find a way to resolve this issue.
I have exactly the same problem. If i disable UserWP i can upload images from backend GD. With UserWP enabled I cannot upload images anywhere to GD. Funnily enough I can still upload images to GD if i use the front end places submission form.
To open a new support ticket, first select the relevant forum and then click the "New Post" button. Example: You need support for the core plugin? Click on Core Plugin support and click on the "New Post" Button.