Like many other companies, Google uses a system called DomainKey Identified Mail (DKIM) to validate that mail sent from Google.com really comes from Google, and not from a scammer pretending to be Google.

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Not clear what happened here, but it seems like either the PO Box was no longer active or the mail clerk sent it back because the box was not registered to somebody named Etux.

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Juliette DeCarteret, the consultant who sent the e-mail about the kickbacks, did not respond to a phone call seeking comment.

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McCain's campaign released an e-mail he sent North Carolina GOP Chairwoman Linda Daves that asked her not to run the ad.

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Walters later sent a follow-up e-mail to Jonathan Wald, advising him not to bother following up with the college graduate, since she did not have an appropriate U.S. visa.

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DePrimo sent an e-mail to Fishman, the parents' lawyer, stating that Kelley was not going to have an abortion.

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