Huh! Turns out there’s an easy way to use a reference Windows installation to create an ISO file. This might not sound like a big deal, but give it some thought. For one thing, it means admins can use a customized Windows 10 installation to spawn as many copies as they like. For another thing, it means power users can snapshot their current installation to create an installer from that image. In turn, this means they can restore or reinstall that image any time they like. Better yet, it’s easy to build install ISO for current Win10 image, if you follow the right steps.
Caveats to Build Install ISO for Current Win10 Image
This approach works only when all elements and user accounts reside on the default Windows drive, aka %windir%. For most installs, this means the C: drive. If any data has been relocated to some other drive, including any or all files or folders for user files, the Documents folder, and so forth, a Windows image file based on the install will not work to (re)install the Windows OS. Unless you’re 100% sure this applies to a reference or target install, you may do the work only to discover that the install doesn’t work. In such a case, it’s best to start over with a clean Windows install and do the work necessary to customize it the old-fashioned way. After that, you can proceed with the steps described to build the custom .wim file confident that it will work the next time you try.
You also need to clean up your system completely before making a snapshot of the image to create the .wim file for the ISO. A TenForums tutorial on this topic is available (follow the instructions in Option Two “To Open and Use Extended Disk Cleanup”). Here again, such cleanup is essential to achieving a successful outcome for your efforts.
The image creation process requires use of the Windows install media, which should be the most current version available. (Visit the Download Windows 10 page to find this.) Boot to the install media, then start the Windows installation process. You’ll press Shift+F10 to launch the Command Prompt window once you see the screen for region and format election. Then you’ll use diskpart to identify your source partition for the Windows image, and the dism (Deployment Image Servicing and Management) command to snapshot your image and create a .wim file. The process is time-consuming and requires close attention to dism syntax, but is otherwise straightforward. The final step is to replace the default (non-custom) install.wim on the Media Creation Tool (MCT) USB with the custom install.wim you just built. After that you can use your customized MCT to install your tailored Windows 10 image as you see fit.
When you see this screen, click Shift+F10 to get into the Command Prompt window…
Get All the Gory Details
The devil is in the details, of course. And that’s where my friend and co-author, Kari Finn, sheds ample light on this subject. His TenForums tutorial on this topic provides nicely-illustrated step-by-step instructions on how to do this. That tutorial is called “Create Windows 10 ISO Image from Existing Installation & Upgrade” and is eminently worth checking out. Then, you too can easily build Install ISO for current Win10 image. Enjoy!