Recover the system from a removable hard disk, use the removable hard disk to make a system image (you can download online) into the BIOS to open the USB boot.

The possibilities of this situation are:

1, windows in the use of the process of error, resulting in the loss of the boot file.

2, the computer was not shut down properly after the last use, resulting in the loss of boot files.

3, Misuse during use, deleted important boot files.

Because of the complexity of the loss of boot files, file type matching, it is extremely difficult to go from a single file to solve the problem, the easiest way is to reinstall the system.

Extended information:

Methods of reinstallation of a computer:

Reinstallation of the system It can be divided into Ghost reinstallation, Microsoft system CD reinstallation, software reinstallation, of which Ghost reinstallation is the most convenient and simple, is the most common method of reinstalling the system.

Ghost reinstallation is the simplest and most convenient way to reinstall a system, which is to download the GHO image of the operating system from the Internet and then reinstall it using the Ghost tool (usually Onekey Ghost), which is easy to use, fast and simple.

The Ubuntu system is now a more convenient way to reinstall the system, just download the Ubuntu boot disk making tool to make Ubuntu boot disk, and then set the Ubuntu boot disk to boot when you enter the system, the making tool can be downloaded from the Internet.

The CD-ROM reinstallation is to directly utilize the CD-ROM to boot directly into the reinstallation option. In the BIOS set to CD-ROM boot or press the relevant shortcut keys to enter the boot menu to select the CD-ROM boot.

Hard drive installation is to download the ISO from the Internet (the original Microsoft version is recommended), and then unzip it to a non-system disk, run the setup.exe program in it, select Advanced and choose the disk drive letter during installation. After that it works in a fully automatic unattended way.

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