I Updated my wordpress from 4.6 to 4.7.2 last night and now i can see that in the post editor in admin panel there is no meta box for selecting the featured images. I also did some editing on the default different image size generation in the settings in here:
I set the meduim and large to 0. I also commented out all my add_image_size() functions in my function.php file in my custom theme.
I would highly appreciate some help. i'm stuck