Unfortunately, at least for Qt 6, the Qt installer's "Qt 6.4 for desktop development" option installs Qt 6.4.0 AND installs only libraries and headers for MinGW-w64; it does NOT install libraries and headers for Visual Studio.
This is not what should be installed if you want to build with Visual Studio.
Equally unfortunately, the Windows setup section of the Wireshark Developer's Guide does NOT warn the user not to select that option and tell the user to go with the default "Custom installation" option.
I will update the documentation.
What you should do is:
- remove the C:\Qt directory;
- run the Qt installer;
- use the "Custom installation" option, which appears to be the default option;
- in the "Custom installation" screen, open up the item for the version of Qt to install - I would recommend that you install 6.2.4, not 6.3.2 or 6.4.0, as Wireshark builds for Windows are currently done with 6.2.4, and there might be problems building with later versions;
- unless you want to take extra time downloading and installing other components NOT required for Wireshark, just select "MSVC 2019 64-bit", "Qt 5 Compatibility Module", and "Qt Debug Information Files";
- do the installation.
