When I go to check on status as explained here I come out the following error even if forms are all active. It can be a problem of configuration variable

Notice: Undefined index: value in theme_status_report () (line 2572 of / web / htdocs / www.wite.it / home / drupal / modules / system / system.admin.inc).
Notice: Undefined index: value in theme_status_report () (line 2572 of / web / htdocs / www.wite.it / home / drupal / modules / system / system.admin.inc).
Notice: Undefined index: value in theme_status_report () (line 2572 of / web / htdocs / www.wite.it / home / drupal / modules / system / system.admin.inc).

I'm following this guide http://drupal-translation.com/content/setup-multilingual-site