While the name tagged to an email sender might suggest "NatWest Bank", a nonsensical email address or one clearly outside the country should raise suspicion.

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Would the investigation have stopped at the discovery of Paula Broadwell as the anonymous email sender?

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" And in such case, "you should destroy this message and kindly notify the sender by reply email.

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An email sender's image and subject line will appear on the device's screen, and users can reply by dictating their messages.

ENGADGET

But the recent ones appear to come from people the target would know and contain text that plausibly could have been written by the alleged sender of the email, he said.

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Even if you recognize the sender, if an attachment is unexpected or looks suspicious, you should confirm that the sender has sent the specific email before clicking on any links or attachments.

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At its core, eSignature eliminates the burdensome process of receiving a document (a contract, non-disclosure agreement, or application, for example) in email, printing it out, signing it, scanning it back in, and returning it by email to the sender.

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So a warrant is required to seize an email as it travels from sender to receiver.

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Once it knew Ms Broadwell was the sender of the threatening messages, the FBI got a warrant that gave it covert access to the anonymous email account.

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