I assume you have already ran the native System File Checker to see if it might find and resolve any issues with system files??
At this stage of the game
You may want to attempt an in-place upgrade / repair install. Upgrading Windows 10 by installing it over top of itself.
There is a pretty good article here
https://neosmart.net/wiki/windows-10-repair-installation/ just ignore the first couple paragraphs where they are promoting their repair products and scroll down to the meat of the article.
If you do not have the installation media....
The installation media can be obtain through either of these two resources.
https://www.microsoft.com/en-us/software-download/techbench
OR
http://www.microsoft.com/en-us/software-download/windows10
Once you have the ISO, you can use ImgBurn to burn it to a DVD or Rufus to burn it to a USB ThumbDrive, or simply mount the ISO from within Windows 10 and run setup.exe from there.
Choose upgrade and make sure the box is ticked to obtain updates as part of the upgrade process.
This is a relatively simple and straight forward task and is generally non-destructive (all your data, programs, drivers, etc., should remain intact and unharmed), but.....
Personally I would still have a backup of my critical data, as well as a disk image, so I could recover in the event of some unforeseen problem.