getimagesize error user meta

Hello everyone! i just downloaded user meta, and created a avatar uploader to my page, and im getting:

Warning: getimagesize(http://mysite.com/wp-content/uploads/2012/04/1335647862.png): failed to open stream: HTTP request failed! HTTP/1.1 500 Internal Server Error in /var/www/web/web543864/mysite.com/wp-content/plugins/user-meta/views/showFile.php on line 22 1335647862.png

How can i fix this?