I having trouble receiving mail in App Engine using the Mail API. I've done it before following the instructions here.
I know that page now says that "This solution is no longer recommended: This page describes how to use a superseded App Engine service. Apps that use this service can only run in App Engine and will need to upgrade to a recommended solution..."; however, the recommended solution page only discusses using a third-party service like Sendgrid (and others) to SEND mail.
I already have a Sendgrid implemented for sending, my need/issue is RECEIVING mail.
Does anyone know if the receiving of email at an @[PROJECT_ID].appspotmail.com address still works or has a new way of being implemented?
After configuring everything, I get no activity in the Mail Handler servlet when I send an email, but I don't get a delivery failure notice either.