A few years ago I received a mail saying that I was the winner of the green card. I was very excited, but when I continued to read the rest of the mail it sounded fishy, it was written that I had to pay a certain amount of money to start the proceedings ($879). That was suspicious, so I contacted people who really got a green card and it turned out that this is another of the many scams on the Internet.

Check twice before you even consider to reply to mail like this. When they ask for money right away, that is most probably a net scam.