Problem solve Get help with specific problems with your technologies, process and projects.

Insider Preview ISOs Add Complexity

Last week, Microsoft released a new Insider Preview — build 15007 — to the fast track. I was not alone in experiencing problems getting that upgrade to download and install. Many people reported problems completing the download successfully (I was in that group). Others reported subsequent failed installations as well. Once upon a time you could grab .esd and other files before the first Windows reboot during the upgrade process. Then, you’d use them to create an ISO file on your own. But the recent adoption of the Unified Update Program (UUP), results in a bunch of files in driving the install. UUP’s file structure now means building Insider Preview ISOs add complexity to the usual contortions previously involved.

Why Does UUP Make Insider Preview ISOs Add Complexity?

Microsoft’s goal with UUP is to slim down the volume of updates by picking (and transmitting) only items that target clients need from Windows Update. Thus, updates (and upgrades) are delivered piecemeal rather than in monolithic form when UUP is active. Working around this limitation involves two potential paths to ISO compilation and alternate installation for Fast Ring users.

The first path comes from one of the gurus at whose nomme de forum is “Kari.” He’s put together a tutorial entitled “UUP to ISO — Create Bootable ISO from Windows 10 Build Upgrade Files.” For DYIers, this approach involves copying the various UUP download files, then compiling them with a tool named UUPtoISO.cmd. This tool builds the ISO for you, after which it will serve nicely on a bootable USB flash drive.

For the Fast Ring, getting ISOs for current builds means building them yourself, or finding them online.
[Image source:]

The other method is to find an alternate source for Fast Track Insider Preview ISOs. My favorite is Sergey Tkachenko’s, which usually provides links to reputable third-party sources when it doesn’t host them itself. Last Friday (1/13) he shared a post entitled “Download Windows 10 Build 15007 ISO images.” It included links to 32- and 64-bit ISO files for Home, Pro, and Enterprise versions of Build 15007.

The Tradeoffs in Insider Preview ISOs Add Complexity

There’s a tradeoff involved in DIY construction vs. ISO download. On the one hand, there’s the time and effort involved in constructing your own. This took me about 22 minutes on my test hybrid tablet (a Dell Venue Pro 11 7130). On the other hand, there’s little time and effort involved in downloading a third-party download except for the download time involved. But one must trust the provider, and absorb the download costs involved. Because that download came from New Zealand, it also took about half an hour to complete.

For me, because I had two machines in the game, one of which succeeded in completing the download, I did have access to the files needed for DIY. Others who didn’t and can’t complete the download can only turn to third parties for downloads elsewhere, or wait for MS to move the build to the slow ring. That’s when they publish official ISOs for the safest possible download option.