diff --git a/package_management.py b/package_management.py
index 61e7ad286..4180a3ffb 100644
--- a/package_management.py
+++ b/package_management.py
@@ -472,7 +472,7 @@ def UpdateSiteDirectory():
     return True
 
   try:
-    AddSiteDirectory(SITE_DIR)
+    EnsureSiteDirectory(SITE_DIR)
     import pkg_resources
 
     # Determine if any packages actually need installing.