Try using a boot disk to restart the computer to see if you can access to hard drive.

试着用启动盘来启动计算机，看是否能访问硬盘驱动器。

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Rather than consigning an old computer to the e-waste scrap heap, give it a new, inexpensive hard disk—or just boot from a CD or a USB flash drive (UFD)—and re-purpose the computer as a thin client.

不必将旧的计算机扔到到电子污染废品站，而是为它提供全新的、便宜的硬盘 — 或从 CD 或 USB flash 驱动（UFD）启动 — 并将计算机重新配置为瘦客户机。

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Then take out your DVD, and try to boot up your computer using hard disk to check if the BOOTMGR is missing problem is solved.

然后拿出你的DVD 安装光盘，并尝试用硬盘重新启动您的计算机，看看bootmgr失踪的问题是否得到解决。

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