没有病毒定义数据库，需要定期更新，没有订阅，没有服务协议。

There is no virus definition database that needs to be updated regularly, no subscription, and no service agreement.

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提供频繁的查杀病毒定义更新，以保持其使用者的安全，由新的恶意软件的爆发。

Avira offers frequent virus definitions updates in order to keep its users safe from new malware outbreaks.

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如果已经装了杀毒软件，请确保你的病毒定义文件为最新的—你可以在杀毒软件厂商的网站上找到该软件的最新更新。

If you have the software installed, be sure to keep your virus definitions up to date-you can find the latest updates on your software manufacturer's website.

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