AnsweredAssumed Answered

delivery not attempted message expired

Question asked by Katie DenHollander on Jan 15, 2015
Latest reply on Feb 13, 2015 by 984db947116dc71becd8d9a9d21469bfca4b2659
I received this message in the Activity Details for several people who soft bounced a recent email "554 5.4.5 [internal] Delivery not attempted (message expired)".

Does anyone know what that means? Did I do something wrong? Does Marketo keep trying to send the email?

This happened to a lot of people on this email, and I don't know how to explain this because I know I will get questions.