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2. Fail Mail
a) When you send an e-mail to the wrong person

b) When you receive someone else's mail.

c) When you receive mail or an e-mail saying you have lost a family member, your house burnt down, you lost your job etc.
a) Oh, crap! I just sent the love letter for the girl I'm cheating with to my wife!

b) Hey, Mr. Nicolas! I got you mail by mistake! I didn't know you were a hooker!

c) I got fail mail from my boss. He fired me for being late yesterday.
1. Fail Mail
A group email from your lecturer/boss/other alerting you and others on the mailing list of your failure.
"Yo, I saw your name on the Fail Mail dude....see you in summer school"
3. Fail Mail
This is not a new term, but a new use for an existing one.

Fail Mail: When a user's email gets stuck in their Outbox and refuses to be sent, for any reason.
John found out why Julia had not received his invitation. There it was, stuck in his Outbox. His beautifully written, sweet, sincere invitation to the girl of his dreams had turned into fail mail.
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