Microsoft OSes will tell you directly if they think your license might be invalid. If you did not get any such message, the OS is probably thinking that the license is okay. So i would not expect the issue beeing about piracy in this case. Also Microsoft is now switching his core business to a much more cloud-based business model. So they also stopped caring about piracy in the last years anyway.
Microsoft's update process became more and more brittle in the last ten years - to the point where they already hat some scandals where companies had to reinstall lots of PCs because they would not boot or get right to the bluescreen after a regular update.
They got absurdly sloppy when it comes to their update process and the update QA. As it is now, most Linux distributions featuring automatic updates are doing them more reliably than Microsoft (it is a real shame because their update process was nearly perfect ten years ago - for the OS itself only of course)...
So yes, could very well be an update. Could also be a hardware failure or anything else of course.
As that OS installation seems to have accumulated quite some history now, i would recommend just getting rid of it.
Backup all the data (might as well backup everything and sort it out later) - twice if you can.
Then do a fresh install of whatever Os you want and chose to reformat the disk while installing it.
After that put some days to good use by reinstalling and configuring all the software you need and sift through the backupped data.
Well, Windows 10 OS has been simply reinstalled with 1803 running. I don't remember exactly what version it had prior to this but it was definitely an older patch running.
So, now it has no errors and everything runs smoothly. Makes me wonder about how reliable some updates (minor or major (such as Redstone)) can be in terms of troubleshooting them with whatever the PC might be running.
To be clear though - none of the data had been removed from the hard drive. It's just sort of "uncoupled" and not installed through the app manager or anything. No registry data through the regedit command invoked through pressing Windows key + R, or icons saved on the desktop/start menu and all that. Almost as if starting from a clean slate.
Thank you kindly for the answer in any case.
Edited by Anderson, 21 July 2018 - 12:19 PM.