So..... both or maybe all user accounts on the system exhibit the same symptoms??
I think that might suggest a more global issue with some operating system corruption rather than a user profile problem.
You might try using the native System File Checker and see if that produces any information.
Right click the start button (if possible) and choose command prompt (admin) and in the command prompt window type
sfc /scannow
hit enter
let it run and see what it says.
Failing that, I think I would try a system restore point to an earlier point in time
Again..... Command Prompt (Admin) and type
rstrui
hit enter
tick the radio button that says "Choose a different restore point"
See if there is a point in time restore, prior to the problem first occurring.
Failing both of the above
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.