Check to see that you have 7 locations for osk.
Here's what I discovered when I went through the computer.
6 folder locations of osk on a 64 bit computer:
I'm not sure why amd64 is in the path because this computer has an Intel CPU. (Ivy Bridge)
C:\Windows\winsxs\amd64_microsoft-windows-osk_31bf3856ad364e35
I have 3 different versions 6.1.7600 and 6.1.7601 followed by 18512 and 22722
C:\Windows\winsxs\x86_microsoft-windows-osk_31bf3856ad364e35
with the same 3 versions.
I found another which Void Tools didn't show:
C:\Windows\SysWOW64\osk.exe
When I "run" osk.exe (I actually right clicked it and looked at all the tabs) and select properties, I see that v 18512 is the version that comes up. It is 676kb and has a date of 17 June 2014.
If you have them at those 7 locations, the next thing to try is a clean boot. This is not the same as booting into safe mode.
It is explained here
https://support.microsoft.com/en-us/help/929135/how-to-perform-a-clean-boot-in-windows
Scroll past the Summary to the section titled How to perform a clean boot and click on Windows 7 and Vista to get screen shots and directions.