diff --git a/packager/app/test/packager_app.py b/packager/app/test/packager_app.py
index 58381fc2aa..6f8b9ef4ad 100644
--- a/packager/app/test/packager_app.py
+++ b/packager/app/test/packager_app.py
@@ -45,7 +45,8 @@ class PackagerApp(object):
     # Put single-quotes around each entry so that things like '$' signs in
     # segment templates won't be interpreted as shell variables.
     self.packaging_command_line = ' '.join(["'%s'" % entry for entry in cmd])
-    assert 0 == subprocess.call(cmd)
+    assert 0 == subprocess.call(cmd), ('%s returned non-0 status' %
+                                       self.packaging_command_line)
 
   def GetCommandLine(self):
     return self.packaging_command_line