Burning windows 7 iso onto a bootable usb and install from it

The following steps work for installing Windows 8 from a usb drive too.

First, you must format the usb drive with NTFS format.

1. Open Command Prompt.
2. Type diskpart and press enter.
3. Type list disk to see the disks that you have.
4. Type select disk 0, replacing 0 with the disk number of your usb drive (look at the disk size as a hint).
5. Type clean.
6. Type create partition primary
7. Type select partition 1
8. Type active to mark it as the active partition.
9. Type format fs=ntfs quick
10. Type exit

After that, mount the Windows 7 installer iso file through Daemon Tools.

Then copy everything in the virtual drive of the iso file into your newly formatted usb drive.

Plug the usb drive into your target pc to install windows 7.

Make sure that the pc boots from the usb drive by setting the boot options or bios accordingly.