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Forum Moderators: phranque
major email software producers would agree
I get 1000 clients each to send 1000 emails to different people all claiming to be from you. Your server now gets hit by 1000*1000=1,000,000 requests for confirmation. In other words, you would be giving the world a superb DDOS tool.
It is all client side so no server modification would be required. It would involve some extra overhead but if it can help reduce spam, the bandwidth benefit would outweigh the extra overhead. The timing point is a valid one. The email won't clear until 2 more receipts are sent and received.:(
Back to the drawing board.