打开PDF、下载PDF时提示：

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https://get.adobe.com/cn/reader/enterprise/ 
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这是因为PDF版本问题导致的。

上面的提示是建议到官网，下载最新版本的软件：

http://www.adobe.com/go/reader_download.

但上面的链接是在线引导安装，下载安装完也不知道软件安装到哪了！

很不方便。

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可以用下面的地址，直接下载安装文件：

https://get.adobe.com/cn/reader/enterprise/ 

在这里可以选择操作系统，版本等，直接下载安装文件。

然后直接在本地安装，就可以了。

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这样还是比较好！