When you have an email message that says "The system is temporarily unable to process your command..." what does that mean? As a customer, that's annoying. As a developer, that's not good.
No software can process all emails. People get notices all the time, including strange kinds like:
"Inda is temporarily unavailable. (Repeat for Inda):"
"The Unicode character � is not allowed in this document." "Coordinator of: "
" 50e0806aeb abrdela