Those redirects deliver a 302 or 301 code, which usually tells search engines to index your error page at many different URLs.

此类重定向提交的是302或301代码，通常这会告诉搜索引擎将你的错误页跟许多不同的URL一起索引起来。

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When you set up your 404 error page, make sure that the server delivers a 404 error code if a page doesn't exist.

在设置404错误页面的时候，一定要确保服务器提交一个404错误代码，如果某个页面不存在的话。

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For example, you've certainly entered a request for a URL, typed the URL incorrectly, and received a 404 error code to indicate a page is missing.

比方说，您肯定遇到过输入了错误的URL请求而得到404错误码的情形，它表示该页面不存在。

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