i tried this on a new installed wordpress server(3.9.1), unfortunately its the same.
But the featured image will be created
- after clicking on posts in the backend,
- or by clicking on archives in the sidebar,
- or by clicking on the category in categories in the sidebar
- or by loading the post directly by clicking on a link in the sidebar
So i think I'm doing something wrong by reading the posts. Could it be that wordpress needs some kind of refresh after uploading?
I'm reading the posts this way in page.php to get all post from one category:
query_posts( 'category_name=pinnwand' );
while (have_posts()) : the_post();?>