Great question from a client today and intelligent feedback worth your knowing ...
Answer from BIT Engineer: "It cannot be stopped any more than a person walking into a bar and saying "Hi, my name is Joe Smith". How does it happen? Easy. Any of the hundreds of people you have ever emailed got infected with a virus/malware that pulled their contact list, which you were a part of. Now that malware has the name of a real live person that it can now use and send email ‘as’ to every one else on that particular contact list."
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