Is there anyway to make an upgrade disc from the Windows 7 RTM ISO? I've done a Google search and site search, but came out with nothing. I've only found that the Ultimate ISO file can be used to install any edition of Windows 7 when the ei.cfg file is deleted or tampered with. But I need to know if it is possible to make the Windows 7 RTM ISO into a ISO that can be used to upgrade from any version of Vista. Thanks, Akaru.