QT: fatal error C1083: Cannot open include file: 'type_traits'

I've been spending almost all day trying to get QT installed on my windows machine. I have installed QTCreator with QT 5.14.1 and QWT 6.1.3 (have also tried 6.2.0) and following these instructions with QWT: https://qwt.sourceforge.io/qwtinstall.html

Everything goes fine until I get to the same point where after running nmake it prints:

qwt.cpp
..\..\..\Qt\Qt5.14.2\5.14.2\msvc2017_64\include\QtCore\qglobal.h(45) : fatal error C1083: Cannot open include file: 'type_traits': No such file or directory
qwt_abstract_scale_draw.cpp
..\..\..\Qt\Qt5.14.2\5.14.2\msvc2017_64\include\QtCore\qglobal.h(45) : fatal error C1083: Cannot open include file: 'type_traits': No such file or directory
qwt_bezier.cpp
..\..\..\Qt\Qt5.14.2\5.14.2\msvc2017_64\include\QtCore\qglobal.h(45) : fatal error C1083: Cannot open include file: 'type_traits': No such file or directory

My path variables show that the include directory where type_traits exists is most definitely there.

Any pointers would be great. I'm not sure what else I can possibly do. I've uninstalled and reinstalled my entire .net framework, same with QT.

Copyright Notice：Content Author:「jabroni」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/74135276/qt-fatal-error-c1083-cannot-open-include-file-type-traits