diff --git a/plugins/dell-dock/fu-dell-dock-i2c-ec.c b/plugins/dell-dock/fu-dell-dock-i2c-ec.c
index 00e8d6baf..4c6b506b7 100644
--- a/plugins/dell-dock/fu-dell-dock-i2c-ec.c
+++ b/plugins/dell-dock/fu-dell-dock-i2c-ec.c
@@ -40,6 +40,7 @@
 typedef enum {
 	FW_UPDATE_IN_PROGRESS,
 	FW_UPDATE_COMPLETE,
+	FW_UPDATE_AUTHENTICATION_FAILED,
 } FuDellDockECFWUpdateStatus;
 
 const FuHIDI2CParameters ec_base_settings = {
@@ -723,6 +724,13 @@ fu_dell_dock_ec_write_fw (FuDevice *device, GBytes *blob_fw,
 				 error_local->message, status);
 			return TRUE;
 		}
+		if (status == FW_UPDATE_AUTHENTICATION_FAILED) {
+			g_set_error_literal (error,
+					     FWUPD_ERROR,
+					     FWUPD_ERROR_NOT_SUPPORTED,
+					     "invalid EC firmware image");
+			return FALSE;
+		}
 	}
 
 	/* dock will reboot to re-read; this is to appease the daemon */