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Microsoft frees up precious storage on Windows 8 with WIMBoot update

WIMBoot. It sounds a bit like something you'd want to purchase before going on a cross-country hike in the snow.

In actuality, it's a new technological technique from Microsoft that arrived as a part of the big Windows 8.1 update this past Wednesday, and it should free up a bit more space on Windows 8 certified devices than your typical operating system installation would otherwise take up.

The catch? Said devices will want to be running speedier flash-based storage — like a 32GB SSD, for example — since the WIMBoot technology will impact performance to an undisclosed degree. And, honestly, WIMBoot is the kind of setup you'll want to run on these speedier, smaller-capacity devices; it wouldn't make much sense for a 500-gigabyte hard drive.

So how, then, does WIMBoot work? In short, it's a tweak on the conventional means of installing Windows on a device.

Instead of unpacking all of the core Windows files from an installation package and dumping them on a partition — which could eat up around nine gigabytes of space on a typical installation (sans recovery image) — the WIMBoot technique dumps this compressed "WIM" file into its own separate "Images" partition.

Windows then creates pointer files within what looks like a conventional Windows installation that actually reference the WIM file on the separate partition.

In other words, you're letting Windows do the work to find what it needs within a compressed archive, as opposed to uncompressing that archive and allowing Windows to more quickly access the core files it's looking for.

"So let's assume the WIM file (INSTALL.WIM) is around 3GB and you are using a 16GB SSD. In that configuration, you'll still be left with over 12GB of free disk space (after subtracting out the size of the WIM and a little bit of additional "overhead"). And the same WIM file (which is read-only, never being changed in this process) can also be used as a recovery image, in case you want to reset the computer back to its original state," writes Microsoft senior product marketing manager Michael Niehaus.

Give how much flak Microsoft has taken over the available space on devices like its Surface tablets, where 14 gigabytes of a 32-gigabyte Surface 2 are sacrificed to Windows overhead, preinstalled apps, and the lot, WIMBoot has the potential to get users quite a bit closer to the advertised capacities of their devices. And that's a good thing.