Leaks of upcoming versions of Microsoft's software are nothing new, but it's a little surprising when the source is Microsoft itself. The Spring update to Windows 8.1, known as Update 1, was briefly available from Windows Update earlier this week.
The update wasn't a free-for-all. To get Windows Update to install it, you had to create a special (undocumented, secret) registry key to indicate that you were in a particular testing group; only then were the updates displayed and downloadable.
After news of this spread, Microsoft removed the hefty—700MB—update from its servers, but not before it had spread across all manner of file-sharing sites...
Just because it was distributed by Windows Update doesn't mean that this is, necessarily, the final build, but it does present a good opportunity to see what Microsoft is actually planning to deliver."
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