diff --git sites/all/modules/boost/boost.admin.inc sites/all/modules/boost/boost.admin.inc
index 0184069..1c64588 100644
--- sites/all/modules/boost/boost.admin.inc
+++ sites/all/modules/boost/boost.admin.inc
@@ -1118,8 +1118,15 @@ function boost_admin_boost_performance_page_submit($form, &$form_state) {
     asort($blacklist);
     variable_set('boost_domain_blacklist', $blacklist);
     unset($form_state['values']['boost_domain_blacklist']);
-
   }
+  else {
+    variable_set('boost_domain_whitelist', array());
+    unset($form_state['values']['boost_domain_whitelist']);
+    variable_set('boost_domain_whitelist_wild', array());
+    unset($form_state['values']['boost_domain_whitelist_wild']);
+    variable_set('boost_domain_blacklist', array());
+    unset($form_state['values']['boost_domain_blacklist']);
+  }  
 }
 
 /**