These are good to keep in handy. In particular, this one: "The integrity of an email message cannot be guaranteed. If a received message seems out of character

These are good to keep in handy. In particular, this one: "The integrity of an email message cannot be guaranteed. If a received message seems out of character for the sender, double-check before taking it seriously." I've come across too many people & organizations who blindly swear by the integrity of an email: "But look, it says right here it was sent by XYZ!"