A knowledge base article about Why did I receive a "delivery status notification (failure)" email when I sent to a bConnected List? provided by the UC Berkeley IT Service Hub - Knowledge Portal
You will only be able to send a message to a list that you have permission to do so. For example, if the list is configured to only allow managers to send to the list, but you are not a manager, you will receive this delivery notification message. Please contact the list manager to request permission to send to the list.
If you are a manager of a list whose members are receiving this message, you may want to update your posting permissions to allow members to send.