Never run an unsigned Vista ISO on bare metal. Use a virtual machine (VMware or VirtualBox) first.
. This allows the aging operating system to run software typically incompatible with it, such as modern versions of Chrome, Firefox, and various Windows 7 or newer applications. Availability & Sources windows vista extended kernel iso exclusive
An ISO file, also known as an ISO image, is a single file that contains a complete copy of a CD, DVD, or Blu-ray disc. In the context of the Windows Vista Extended Kernel, an ISO file is used to distribute the customized kernel as a bootable image that can be burned to a physical medium or mounted as a virtual drive. Never run an unsigned Vista ISO on bare metal