That’s pretty mysterious then. If you have access to your server’s error log that would help.
If you haven’t you could turn on WP_DEBUG to do that:
* login to your site via FTP
* download the wp-config.php file
* duplicate this file to create a backup (just in case something goes wrong)
* replace this:
define(‘WP_DEBUG’, false);
/* That’s all, stop editing! Happy blogging. */
* with this:
define(‘WP_DEBUG’, true);
/* That’s all, stop editing! Happy blogging. */
* save and re-upload this file to your site.
Then you can log the errors and we can figure out exactly what is going on. You probably won’t want to leave WP_DEBUG enabled for very long – just long enough to log the errors for this issue unless this is on a testing/development server.