My computer went from running great under 1607 to locking constantly after a few minutes with 1709. I tried disabling "Fast Startup" but that didn't work. Fortunately, I was able to use Windows' Recover feature to roll-back to 1607. It now works great. Microsoft views Windows 10 as a "service" so that's how they justify installing updates/"upgrades" without our consent. Fortunately, there's a way to stop this. I've put the link below and I used the "Local Group Policy Editor" to easily stop these from being installed without my consent.
https://www.windowscentral.com/how-stop-updates-installing-automatically-windows-10
Here's another article on how to prevent major "upgrades".
I feel now that I've taken back control of my PC. I can't believe Microsoft puts out such buggy software that breaks peoples computers that they use for important work without the users' consent. I was about to buy a Mac if I couldn't get this situation under control. Now, my next issue is stopping Windows 10 from changing my default programs, especially pdf's, to Microsoft Edge, but I've found online ways to stop this, too.