It so happened this week that my old favorite USB 3.0 pendrive stopped working. I have used it to install Windows a zillion times. I have USB 2.0 pendrives but they are very slow when copying or reading files. So I decided to use my external hard drive as the installation media to install Windows 10 on my new laptop. Here are the steps I took to successfully install Windows 10 using an external hard drive:
Note: Before beginning, make sure that you have downloaded Windows 10 ISO image from Microsoft servers and have installed 7-Zip in your PC. The external hard drive should have only one MBR partition (you can use MiniTool Partition Wizard to create an MBR partition). If you have some files on the external hard drive, make a backup of these files on some other device.
- Attach your external hard drive to your PC using the USB cable.
- Right-click on the external hard drive in File Explorer and select Format. Select file system to be NTFS and choose Quick Format in the formatting dialog.
- Right-click on the Windows 10 ISO image file, select 7-Zip → Open Archive. Then extract all the files from the ISO to the external hard drive.
- Open an elevated command prompt. Assuming F: is the drive letter for your external hard drive, give the following commands:
f: cd boot bootsect /nt60 f: /force
- Now we have to use the diskpart tool to make the partition on external hard drive bootable. For this, in the elevated command prompt we give these commands:
diskpart list disk select disk 1 list partition select partition 1 active exit
Assuming that “list disk” displays the external hard drive as the disk no. 1 and the “list partition” displays the partition no. 1 for the first partition in the external hard drive.
- Now you can reboot your PC and when press F12 to select a boot media when the PC is about to start. Select the “Mass Storage Media” from the list to start the Windows 10 installation.
If your computer is not able to boot using the external hard drive, then try turning off the PC and the external hard drive both first and then power them up at the same time. This is because some portable hard drives stop spinning when Windows is rebooted.