Yes exactly the same problem. According to media manager it has uploaded but. there is no thumbnail and image on specified folder. When i upload image via ftp it works. Is it a bug on 2.9.1?
thanks.
worked for me too thank you 🙂
I have same problem. Version is 2.8.2
Warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, 'media_admin_css' was given in .../wp-includes/plugin.php on line 339
