Got a low-cost laptop? Windows 10 upgrade may take some effort

Now that Microsoft has opened up the floodgates to try the Windows 10 Technical Preview, you’re itching to give it a go, right? So am I, so I attempted to get the latest software through the Windows Insider program.

These days, I’m using the $229 HP Stream 13 — a low-cost but capable Windows 8.1 with Bing laptop — but my first attempt to upgrade went awry. So will yours if you have an inexpensive computer or tablet that has a minimal amount of flash storage capacity.

The HP Stream 13 comes with 32GB of local storage and meets all of the hardware specifications [company]Microsoft[/company] lists to run Windows 10 so, I didn’t think I’d run into any problems. (Note: I did create a recovery image of Windows 8.1 on a tiny microSD card just to safe, of course.) But a technique Microsoft uses to help free up more storage on devices actually interferes with the Windows 10 preview upgrade, as shown by this screen that stopped me in my tracks:

Windows 10 upgrade fail

When the Windows 10 Technical Preview Setup app checked my computer before upgrading, it said Windows 10 can’t be installed because the computer uses a compressed operating system.

wimboot free space

This pertains to something called WIMBoot, or Windows Image File Boot, which essentially lets Microsoft squeeze Windows into a smaller space on your hard drive or flash memory; perfect for low-cost devices with limited storage. Without WIMBoot, the operating system uses up more of that free space.

windows without wimboot

Here’s how Microsoft describes WIMBoot:

In a standard Windows installation (without WIMBoot), every file is written to disk at least twice: once in the compressed form for recovery, and once in the uncompressed form in the applied image. When the push-button reset feature is included, the compressed image remains on the PC. Having both the Windows installation and recovery image on the device can take up a lot of disk space.

When installing Windows with WIMBoot, you write the files to the disk only once, in compressed format. Next, you apply a set of pointer files onto the Windows partition that point back to the compressed files in the Images partition. When the user adds files, apps, or updates, they’re added onto the Windows partition. In WIMBoot, your WIMBoot image is also used as the recovery image, saving disk space.

That’s great for everyday use but not so much if you want to try the Windows 10 Technical Preview on a laptop or tablet with meager storage capacity. InfoWorld’s Woody Leonhard ran into the same issue on a brand new Asus Transformer 2-in-1 computer but says there’s no workaround.

At this point, I suspect I’ll have to download the Windows 10 image directly from Microsoft as an .iso file and copy it to a bootable flash drive. That approach should wipe Windows 8.1 with Bing — compression and all — from the computer and install, not upgrade, a clean copy of the Windows 10 Technical Preview, which is a bit more work.

That’s OK, I’m willing to put in the effort so I can check out Microsoft’s latest and greatest; even on my limited $229 laptop.