I see many people asking what my question has to do with QT. The problem is that I use QT for an application which has to run on Macintosh, Windows and Linux and it must be able to read a USB. Original it was a Windows VC++ application and I want to get rid of that completely hence I started to redo all in QT. Many users still use the original application and therefore we have to be able to have the QT version to run on Windows as well.
OK, but your question at the beginning is about how to make those specific Win32 headers and functions work. And it is independent of use of Qt.
If any person here can advise how I can read the USB information (Serial number, provider, other information) I would very much appreciate it.
Try looking for libusb and/or LibUsb-Win32.