Those pushhy bastards at Microsoft really, really want to upgrade every Windows 7, 8 and 9 into a 10. (Yes, Windows 9 doesn't exist.) They even re-released KB3035583 to make sure that any previous blocking since March 2015 wouldn't be affected anymore. This is what my Windows 7 started doing:
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This wasn't supposed to be happening. See details of Part 1. I downloaded latest version of GWX Control Panel, I think it is 1.7.3, but it showed nothing special:
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There were some deleted Windows 10 files and a single process running, but I re-zapped them with GWX CP. That didn't make the KB3035583 disappear from the updates list.
A solution to make it gone was simpler than I originally thought:
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Just selecting Hide update will make it stay gone. I guess MS-guys will be re-re-releasing it eventually, but for the time being, I'm happy with the result.