diff --git contrib/search_api_views/includes/display_facet_block.inc contrib/search_api_views/includes/display_facet_block.inc
index e0e2276..fc28d1b 100644
--- contrib/search_api_views/includes/display_facet_block.inc
+++ contrib/search_api_views/includes/display_facet_block.inc
@@ -98,7 +98,19 @@ class SearchApiViewsFacetsBlockDisplay extends views_plugin_display_block {
 
   protected function getFieldOptions() {
     if (!isset($this->field_options)) {
-      $index = search_api_index_load(substr($this->view->base_table, 17));
+      $index_id = substr($this->view->base_table, 17);
+      if (!($index_id && ($index = search_api_index_load($index_id)))) {
+        $msg = 'DEBUG: views base table: ' . $this->view->base_table;
+        if ($index_id) {
+          $msg .= "\nPlease control if this is an index: " . l('click', 'admin/config/search/search_api/index/' . $index_id);
+        }
+        drupal_set_message($msg);
+        $table = views_fetch_data($this->view->base_table);
+        $table = empty($table['table']['base']['title']) ? $this->view->base_table : $table['table']['base']['title'];
+        throw new SearchApiException(t('The "Facets block" display cannot be used with a view for !basetable. ' .
+            'Please only use this display with base tables representing search indexes.',
+            array('!basetable' => $table)));
+      }
       $this->field_options = array();
       if (!empty($index->options['fields'])) {
         foreach ($index->options['fields'] as $key => $field) {