Microsoft can't seem to get KB 3022345 straight.
Two weeks ago it released version 1 of the Windows patch, specifically directed at Windows 8.1 PCs. Then on May 5 we got version 2, apparently directed at Windows 7. Yesterday Microsoft released version 3, and although the KB article says it's now an equal-opportunity Windows 7/8.1 patch, it's only showing up on Windows 8.1 PCs.
A few eagle-eyed patchers took the beast apart and discovered the patch is … wait for it … a usage tracker. (Perhaps another patch paving the way for Windows 10?)
You have to wonder how Microsoft would have pulled off the same rapid-fire sequence in a Windows 10 Fast-ring/Slow-ring/WUB world.
Retracing the patch's history, on April 21 Microsoft released KB 3022345 -- an "update to enable the Diagnostics Tracking Service in Windows 8.1 and Windows Server 2012 R2." The next day many reports began to appear that the installer failed with error 800F0922. On May 5 Microsoft re-released the patch, changing its title to "Update to enable the Diagnostics Tracking Service in Windows." Apparently that second version was directed at Windows 7 (at least it appears, dated May 5, on my Windows 7 PCs). On May 6 Microsoft re-re-released the patch, this time with hints that version 3 is intended for Windows 8.1 (it appears, dated May 6, on my Windows 8.1 PCs).
To date, the only information we have about the patch is the summary in version 2 of the KB article:
This update enables the Diagnostics Tracking Service in Windows 8.1, Windows Server 2012 R2, Windows 7 Service Pack 1 (SP1), and Windows Server 2008 R2 SP1. This tracking service collects data about functional issues in Windows.
If you open the update file for version 3 you see these files (t/h SB):
JSON files, you may know, are used to describe data sent back and forth between the server (in this case, Microsoft servers) and the client (which is to say, you).
You can see the JSON files and their contents for yourself, if you're curious. Download the appropriate patch from Microsoft's download site (Windows 8.1 x64), extract the MSU file using the instructions in KB 934307, then extract the CAB files. You'll find a folder named (in the case of Win81 x64) amd64_microsoft-windows-u..ed-telemetry-client followed by a bunch of numbers. Look inside and open up the JSON files with Notepad.
Is it time to pull out the tinfoil hats and run for cover? I don't think so.
But life would be so much easier if Microsoft would tell us what it's doing with these mystery patches and let us decide for ourselves whether we want to install them.