Editor's note: Many ultra-thin notebooks are not equipped with optical drives, which is very inconvenient to install a new operating system, and Windows supports installing the operating system directly from the mobile hard disk. This article describes the specific process in detail. . Starting with Windows Vista, Microsoft has made adjustments to the way its operating system is deployed, making it easier and faster for individuals or businesses to install in large quantities. In terms of the normal CD-ROM installation method, in the past, the XP operating system was installed. No matter how high the machine configuration is, it takes at least 50 minutes to complete the installation, and the hard disk space occupied by the installation is less than half of the vista, and since Windows Vista, Microsoft started. The installation of the operating system has been greatly improved, which has greatly shortened the installation time. Take Microsoft's latest operating system, Windows 7, as an example. The normal CD installation takes about 30 minutes, and the USB flash drive takes about 18 minutes. The mobile hard drive installation is shorter, it only takes 13 minutes. (These data are the data I personally installed and tested on my laptop. It may not be universal.) Of course there are other ways to install the speed. It is also faster, such as hard disk installation through pe, or virtual optical drive loading and installation under the existing system, etc., but the ultimate goal is to install it in a simple way and at the fastest speed, so much, I just I want to explain that the method of installing Windows 7 with a mobile hard disk is my current most Commonly used installation methods, then this post I will specifically talk about the way to install Windows 7 on the hard disk. 1. First of all, you need to have a mobile hard disk, insert it into the USB interface of the computer, and then set any partition of the mobile hard disk to “active”, here we take “execution” as an example. This step is done on the desktop: right click on the computer, select - manage, then the "Computer Management" program window will open, then select - Disk Management, find the h drive, then right click, then Select “mark the disk partition as active” option, complete the program window. Next, in the Explorer of the computer, right-click the h disk and select Properties to see if disk compression is enabled. If enabled, be sure to compress the drive to save disk space under the General tab. The previous check is canceled. (This step is very important, if you do not cancel, the system will not be able to boot from the mobile hard drive installation). 2. Extract or decompress the Windows 7 CD image file you downloaded to the h disk. After the decompression is completed, restart the computer and set the boot order of the computer to usb -hd (in general, the computer will automatically recognize your mobile hard disk. The model selection can be started by this drive), at this time the computer will start the installation program from the mobile hard disk and start the installation of Windows 7. 3. If the machine is purchased after 2007, it usually takes no more than 16 minutes from startup to entering the system desktop. Supplementary note: I have done this myself. I can say that I have said it is very detailed. The installation is very fast. Just like the installation of the CD, you can format the partition. If your computer cannot boot from the mobile hard disk, please check the above steps. Have you done it, and whether your machine supports the booting of the usb device.