Wordpress Featured Image Not Working

I have in开发者_StackOverflowstalled the the_post_thumbnail function into my function.php file. The GUI for the function pops up when I am editing posts, however, whenever I upload a pic, I receive a broken image/link and nothing is actually uploaded. Does anyone know why? Anyone with a similar experience know a quick fix?

Check in other browsers if you are using Chrome, because I had the same issue with Chrome, switch to Safari or you can use Advanced Custom Fields instead of using the Featured image.