# Config issues with Qt and Visual Studio

A recent Windows 10 update manage to break my Visual Studio installation and also my Qt installation.. Forcing me to reinstall and face some configuration issuses.

## Environment Vars

For whatever reason the Windows update decided it was a good idea to change all of my environment variables to point to the C drive instead of my D drive. I had to manually determine which pathes were valid.

## Qt MSVC Environment Setup

The first error encountered was Qt not being able to initialize the VS environment. I got the following error:

Failed to retrieve msvc environment from vcvarsall.bat


vcvarsall.bat is located at D:\Program Files (x86)\Microsoft Visual Studio 14.0\VC. It initializes the Visual Studio environment.

This batch file requires the VS140COMNTOOLS environment variable to to set (One of the variables change by the update). Ensure that it points to The correct directory.

For example: D:\Program Files (x86)\Microsoft Visual Studio 14.0\Common7\Tools\

vcvarsall.bat reads from the registry to find information about Visual Studio. Due to the update, or perhap incorrect installation, the registry value was not set correctly.

To edit the registry open run dialog (Win + R) and type regedit. Navigate to Computer\HKEY_LOCAL_MACHINE\SOFTWARE\WOW6432Node\Microsoft\VisualStudio\SxS\VS7 and ensure the values present are correct.

This allowed Qt to initialize the Visual Studio environment.

## Missing include type_traits

Qt then gave this error:

D:\Qt\5.9.2\msvc2015\include\QtCore\qglobal.h:45: error: C1083: Cannot open include file: 'type_traits': No such file or directory


I should have noticed this sooner but it wasn’t super apparent at first. The include path shown indicates it was using the MSVC 2015 build kit. But since I had reinstalled I was using the MSVC 2017 compiler.

Qt will pick several build kits to build against when you setup a project. Ensure the build kits selected actual have valid compilers on your system.