--- a/Programs/brlapi.h.in
+++ b/Programs/brlapi.h.in
@@ -138,7 +138,7 @@ size_t BRLAPI_STDCALL brlapi_getHandleSi
 /* No authentication by default on Windows */
 #define BRLAPI_DEFAUTH "none"
 #else
-#define BRLAPI_DEFAUTH BRLAPI_ETCDIR "/" BRLAPI_AUTHKEYFILE
+#define BRLAPI_DEFAUTH "polkit+keyfile:" BRLAPI_ETCDIR "/" BRLAPI_AUTHKEYFILE
 #endif /* BRLAPI_WIN32 */
 
 #ifdef __MINGW32__
