diff --git a/action_processor.h b/action_processor.h
index a395b3d..98fc853 100644
--- a/action_processor.h
+++ b/action_processor.h
@@ -34,6 +34,7 @@
   kActionCodeKernelDeviceOpenError = 8,
   kActionCodeDownloadTransferError = 9,
   kActionCodeDownloadHashMismatchError = 10,
+  kActionCodeDownloadSizeMismatchError = 11,
 };
 
 class AbstractAction;