Master Massimo, Perfect !, you are right !. Follow the correct configuration to solve this(my) problem(sent mail) in this situation: app deployed in GAE and domain managed by Google Apps:
in db.py mail=Mail() mail.settings.server='gae' mail.settings.sender='yourMailAccountInAppEngine' # The account that you use to deploy the app in GAE. in the controller: mail.send(to=['theMailAccountToSend'],subject='Hello World',message='Hello World Message') Thank you very much !. -- Leandro.