diff --git a/src/calibre/library/caches.py b/src/calibre/library/caches.py
index be996063d5..19ef7e213c 100644
--- a/src/calibre/library/caches.py
+++ b/src/calibre/library/caches.py
@@ -583,6 +583,8 @@ class ResultCache(SearchQueryParser): # {{{
             candidates = self.universal_set()
         if len(candidates) == 0:
             return matches
+        if location not in self.all_search_locations:
+            return matches
 
         if len(location) > 2 and location.startswith('@') and \
                     location[1:] in self.db_prefs['grouped_search_terms']: