I am working in a new project, and I just realized that in the page/post edit pages, I don´t have the option to set a featured image/ post thumbnail.
I have checked and Twenty Ten has thumbnails support by default ( add_theme_support( 'post-thumbnails' is in functions.php). I also tried setting the thumbnails size with set_post_thumbnail_size, but no luck.
P.D: I installed this in a new server, is it possible that it has something to do with that? Are there any specific requirements to use post thumbnails?