While email is fairly reliable, messages do get lost. This can be due to the store-and-forward nature of email, which passes responsibility for delivering email from one mail server to another, but in doing so exposes messages to loss, should a server not fulfil its responsibility. Some end users are more sensitive to email unreliability than others, and seek tools with which they can detect and recover from email failures. This paper describes tools that allow email sending software to automatically respond to reports of undeliverability by persisting with retransmission or retransmitting to alternate recipients.