Email accounts based on POP, IMAP or exchange can be configured manually as well as using the secondary email application available with Android.

用户可以手动地配置基于POP、IMAP或Exchange的email帐户，也可以使用Android提供的辅助电子邮件应用程序进行配置。

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There can be secondary authorities holding the public key in case the email provider does not want to implement the protocol or it is not reliable.

为了防止邮件提供商不想实现这个协议或者它是不可信的，还可以由第三方认证机构来持有公钥。

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However, the company said it would text a provided number or email a secondary email address to warn users before any action is taken.

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Well, not likely, but it could make email secondary, Goens suggested.

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For example, in a standard phishing operation, an organized crime group might commission the creation of a scam web page and contact a secondary broker to get a list of thousands of email addresses.

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