diff --git a/src/AddIns/BackendBindings/Ruby/RubyBinding/Project/Templates/WPFApplication.xpt b/src/AddIns/BackendBindings/Ruby/RubyBinding/Project/Templates/WPFApplication.xpt
index a165b84dce..dde2f040bb 100644
--- a/src/AddIns/BackendBindings/Ruby/RubyBinding/Project/Templates/WPFApplication.xpt
+++ b/src/AddIns/BackendBindings/Ruby/RubyBinding/Project/Templates/WPFApplication.xpt
@@ -28,7 +28,7 @@
 		<PropertyGroup configuration="Release" escapeValue="false">
 			<OutputType>WinExe</OutputType>
 			<MainFile>Application.rb</MainFile>
-			<StartArguments>--disable-gems Application.py</StartArguments>
+			<StartArguments>--disable-gems Application.rb</StartArguments>
 			<StartWorkingDirectory>.\</StartWorkingDirectory>
 			<StartAction>Program</StartAction>
 			<StartProgram>${addinpath:ICSharpCode.RubyBinding}\ir.exe</StartProgram>