We have already shown various ways to install and test Windows 8.1 and the latest version of Windows 10 on your PC, including how to install Windows 10 from USB drive, how to clean Windows 10 installation from ISO, create Windows 10 bootable UEFI USB etc. .
Since many readers ask to write their best to install Windows 8.1 or Windows 10 from an external hard drive, we have created this simple guide to show you how to install Windows 10 or 8.1 from an external hard drive.
A backup of critical data on the external hard drive is recommended as the method requires formatting the external drive.
NOTE: In this guide, we use a Windows 7 PC to prepare the bootable external hard drive. The procedure is practically the same in Windows 10 and 8.1.
Make external hard drive bootable to install Windows 10 / 8.1
Step 1: Connect the external USB hard drive that you want to use as the installation media to your PC and back up your data in a safe place, as the drive will be erased in the following steps.
Step 2: Open computer, the right button of the mouse external hard drive icon, then select Format option to open the Format dialog box. Select File system as NTFS, To select Quick format option and click Start to perform a quick format of the drive.
Click Yep for the confirmation request. After formatting is complete, you will see «Full format“Message. Click on OK button.
Step 3: We assume you have a Windows 10 / 8.1 ISO file. You must extract the contents of the ISO file to the root directory of the external drive. To do this, you need 7-Zip (free), WinZip, or WinRAR software.
If you have one of the above-mentioned zip utilities on your PC, right-click the Windows 10 / 8.1 ISO file and select Extract Archive option to extract the contents of the ISO file to the external hard drive.
NOTE: If you are using 7-Zip software to extract the ISO file, the right button of the mouse in ISO> 7 zipper > Extract the files option. Make sure to extract the files to the root directory of the external hard drive.
And if you have a Windows 8.1 or 10 DVD, just copy all the files and folders from the DVD to the root of the external hard drive.
Step 4: Now open the command prompt with administrator privileges. To open the command prompt with administrator rights, you can do one of the following:
A. type CMD in the Start menu search box and press Ctrl + To exchange + login in keys simultaneously.
SECOND.. Go Start > All the programs > Accessories. Right-click the command prompt entry and select Execute as an administrator option.
Step 5: At the command prompt, type the following commands and press the Enter key after typing each command.
cd / boot
(where “x” is the letter of the external hard drive)
(this is the message you receive once the process is complete)
Step 6: Exit the command prompt, restart your PC, and follow the onscreen instructions to install Windows 10 or Windows 8.1 from the external hard drive.