Have anyone ever noticed this error message --> MAPI_E_NETWORK_ERROR (80040115). This is relevant to Exchange. I have a monitoring application (Mail Attender )that attempts to send an email message to a mailbox and the message is never received. However, this error message reports to the logs of the application sending the message that it has received a MAPI_E_NETWORK_ERROR (80040115) error message. Any reconmendations?