diff --git a/src/vm/VirtualMachine.cc b/src/vm/VirtualMachine.cc
index 5d5595b7f4..e56c197029 100644
--- a/src/vm/VirtualMachine.cc
+++ b/src/vm/VirtualMachine.cc
@@ -1216,7 +1216,7 @@ error_saved:
     goto error_common;
 
 error_image_id:
-    oss << "The DISK " << disk_id << "does not have a valid IMAGE_ID.";
+    oss << "The DISK " << disk_id << " does not have a valid IMAGE_ID.";
     goto error_common;
 
 error_not_found: