diff --git a/xpinstall/res/locale/en-US/xpinstall.properties b/xpinstall/res/locale/en-US/xpinstall.properties
index f9debffac7b3..e74a36dd5a81 100644
--- a/xpinstall/res/locale/en-US/xpinstall.properties
+++ b/xpinstall/res/locale/en-US/xpinstall.properties
@@ -51,6 +51,10 @@ Patch=Patching: %s
 
 Uninstall=Uninstalling: %s
 
+RegSkin=Register Skin: %s
+RegLocale=Register Locale: %s
+RegContent=Register Content: %s
+RegPackage=Register Package: %s
 
 #--------------------------------------------------------------------
 #   Dialog Messages