diff --git a/inc/caldav-OPTIONS.php b/inc/caldav-OPTIONS.php
index b3a1fa30..5d2a36a2 100644
--- a/inc/caldav-OPTIONS.php
+++ b/inc/caldav-OPTIONS.php
@@ -41,7 +41,7 @@ else {
   }
 }
 
-if ( !exists ) {
+if ( !$exists ) {
   $request->DoResponse( 404, translate("No collection found at that location.") );
 }