“This update performs diagnostics on the Windows systems that participate in the Windows Customer Experience Improvement Program. But as InfoWorld puts it, the switch from Optional to Recommended can be done at any point, and with Patch Tuesday taking place this week, this seems to be the best moment to do it. This is the reason they aren’t enabled by default in Windows Update, but only offered as optional, which means that users need to manually check and install them. All versions of Windows 7 and Windows 8.1 are getting the two patches in Windows Update. In other words, they’re telemetry updates that help Microsoft collect data from systems participating in this program, and installation only takes place with users’ consent.
The two updates are KB2952664 and KB2976978 and are aimed at Windows 7 and 8.1, respectively, with Microsoft explaining in the rather vague description posted on the official KB pages that they’re only supposed to be installed on systems enrolled in the Windows Customer Experience Improvement Program. Microsoft has quietly re-released two updates to Windows systems, though there’s a good chance that only a few users would end up installing them because they’re not enabled by default.