[Plugin: W3 Total Cache] Empty page cache problem

You need to enable WP_DEBUG to see the cause of the error you are getting. Open your wp-config.php file and add this line:

define( 'WP_DEBUG', true);

Then go and try to reproduce the error noting the detailed error message output to the screen.

You should also deactivate all other plugins and switch to the default theme to determine another plugin or your theme causing the problems.