E-mail scanning should be a transparent process, with no perceivable delay in email performance and should also be scalable - able to manage 10,000 users as easily as it can manage 100.

电子邮件扫描应当是个透明过程，不会对邮件造成明显的延迟，并且应当是可测量的——管理10000用户或者100个用户一个样。

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Many approaches involve scanning incoming data for possible malware and screening spam e-mail laden with viruses or containing suspicious messages.

这些方法包括扫描传入数据以防有恶意软件和扫描携带有病毒和包含可疑信息的e-mail。

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It offers automatic e-mail scanning and handy update features.

CNN: The best products of 2000

Schrader said the best defense against Trojan Horse e-mail viruses is end-user education -- and, of course, updated virus-scanning software.

CNN: New 'Trojan Horse' strain may go mainstream