I had a customer complain to me a little while back. Everytime, he would restart his computer his Number Lock on his keyboard would not stay enabled. Here is what I did to fix his issue. 

P.S. This also worked on my personal Windows 10 1607 computer. 

Step One: 

• Change the value of HKEY_Users/<UserProfiles>/ControlPanel/Keyboard/InitialKeyboardIndicators to 2147483650 for ALL USERS profiles not only for .Default. 

Step Two: Once the above edits in the Registry have been completed. Shutdown the computer.

Step Three: Turn on your computer and wait for login screen (NumLock is still off). Log into your computer.

Step Four: Enable NUMLOCK and shutdown your computer.

Step Five: Turn on your computer. NumLock should now be enabled.

Let me know if the above solution works for you. Hat Tip to this Reddit Thread. 

I hope this helped. If it did please let a comment below! You can follow me on Twitter and subscribe to my YouTube Channel. This was posted by techspeeder.