diff --git a/OMPython/__init__.py b/OMPython/__init__.py
index 2177dbc..67776a7 100755
--- a/OMPython/__init__.py
+++ b/OMPython/__init__.py
@@ -528,7 +528,7 @@ def getClassNames(self, className=None, recursive=False, qualified=False, sort=F
                                  str(builtin).lower(), str(showProtected).lower()))
         else:
             value = self.ask('getClassNames',
-                             'recursive={1}, qualified={2}, sort={3}, builtin={4}, showProtected={5}'.format(
+                             'recursive={0}, qualified={1}, sort={2}, builtin={3}, showProtected={4}'.format(
                                  str(recursive).lower(), str(qualified).lower(), str(sort).lower(),
                                  str(builtin).lower(), str(showProtected).lower()))
         return value