diff --git a/chaos_monkey/build_windows.bat b/chaos_monkey/build_windows.bat
index 57435ce7c..8f2267361 100644
--- a/chaos_monkey/build_windows.bat
+++ b/chaos_monkey/build_windows.bat
@@ -1,2 +1,2 @@
 REM c:\Python27\python -m PyInstaller.main --name monkey -F -y --clean -i monkey.ico main.py
-c:\python27\Scripts\pyinstaller --log-level=DEBUG --clean --upx-dir=.\bin monkey.spec
+c:\python27\Scripts\pyinstaller -F --log-level=DEBUG --clean --upx-dir=.\bin monkey.spec