This tutorial will help you with the installation of Windows from image (.iso and .img) file using USB Drive.
Windows 7
Windows 7 Professional Full Version Free Download ISO [32-64Bit]
Windows 7 Professional Download Free Free Download Latest OEM RTM version. It is Full Bootable ISO Image of Windows 7 Professional Free Download.
Windows 7 Enterprise Download Free
Windows 7 Enterprise Free Download ISO 32 Bit 64 Bit direct links. It is full bootable official untouched Windows 7 Enterprise 32 bit 64 bit Free ISO Image.