A powerful email client software, it can be annex there is a wide variety of system code conversion.

一个功能强大的邮件客户端软件，可以发附件还有各种码制的转换。

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For starters, the couple could have used stress-tested PGP (Pretty Good Privacy) for point-to-point encrypted email which involves installing a separate piece of client software and the exchanging of public keys.

FORBES: The General, The Biographer, And Unencrypted Email