No worries, here are few tips and online services that may still help you uncover the identity of that unknown email sender.

别急，这里仍有一些揭开未知邮件发送者身份的方法与在线服务。

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Now paste the IP address in this trace route tool and you should get a fairly good idea about the location of the email sender.

然后将ip粘贴到本路由跟踪工具，您应该可以大体知道邮件发送者所在地了。

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The third preference is for the sender email address.

第三个首选项是发送者电子邮件地址。

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

FORBES: The General, The Biographer, And Unencrypted Email

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

ENGADGET

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.

BBC: Q&A: Phishing for your precious data