sators

You might be able to find troubleshooting info by making these edits temporarily to your wp-config.php:

define('WP_DEBUG', true);
define('WP_DEBUG_LOG', true);
define('WP_DEBUG_DISPLAY', true); 

In my case, I did not have the php-xml module installed on the server and it was failing.

Figurd out a fix: http://blog.mattsatorius.com/technology/web-design/wordpress-gallery-shortcode-with-no-image-link/

Got the same error…although this is what I did to get it to work:

For the host – instead of putting in my normal http://ftp.domain.com address, I put in “localhost” without the quotes. Same username/password as my FTP user and whala. Worked.

Give it a try. Depending on your hosting server setup, this may not work, but worth a shot.