Feauterd image meta box not showing up

Question

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

Answer 1

I find the problem i had accidentally deleted this function in my functions.php file in the theme directory.

add_theme_support('post-thumbnails');