After Win7 to Win10 I have "MISSING references"

[sts023]

Hi again....



My Win7 Desktop PC went to the great recycling yard in the sky, and I have a new Windows 10 PC.
It came with a 30 day trial of Office 365, which I uninstalled and instead installed my previously purchased version of Office 2010.

On attempting to execute some Word VBA, I got dire warnings about needing PtrSafe on some Function declarations (why??? - my Win 7 pc was 64 bit, and the Win 10 is 64 bit - ???).

Having edited the declarations to include PtrSafe, when Recompiling I get "Can't find Project or Library", and in my References I have "MISSING: Microsoft Windows Common Controls-2 6.0 (SP6)".

I've tried Googling this Reference, but to no avail.

I can uncheck it to stop the error, but should I actually be installing it?

Does anyone know what it is, what it does, and if I need it?