LNK1107: Invalid or damaged file: reading at 0x2E0 not possible

Hello,

I only have a .DLL file from an external source. No .lib or .h. This is why I am using LoadLibrary (QLibrary)- I was reading that if I only have the .dll I have to do it like that.

I know the functions but dont know how to implement the Dll correctly.

This ist what I tried:

.pro

Code:

QT       += core gui
 
greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
 
CONFIG += c++14
 
LIBS += "C:\Users\lauer\Qt_Projects\build-firsttry32bit_gebiom-Desktop_x86_windows_msvc2019_pe_32bit-Debug\debug\GP_MUX_MODAWIFI.dll."
 
 
SOURCES += \
    main.cpp \
    mainwindow.cpp
 
HEADERS += \
    mainwindow.h
 
FORMS += \
    mainwindow.ui
 
# Default rules for deployment.
qnx: target.path = /tmp/$${TARGET}/bin
else: unix:!android: target.path = /opt/$${TARGET}/bin
!isEmpty(target.path): INSTALLS += target

main.cpp

Code:

#include "mainwindow.h"
 
#include <QApplication>
#include <QLibrary>
#include <QDebug>
 
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
 
    if (QLibrary::isLibrary("C:/Users/lauer/Qt_Projects/build-firsttry32bit_gebiom-Desktop_x86_windows_msvc2019_pe_32bit-Debug/debug/GP_MUX_MODAWIFI.dll")) { // GP_MUX_MODAWIFI.dll
          QLibrary lib("C:/Users/lauer/Qt_Projects/build-firsttry32bit_gebiom-Desktop_x86_windows_msvc2019_pe_32bit-Debug/debug/GP_MUX_MODAWIFI.dll");
          lib.load();
          if (!lib.isLoaded()) {
            qDebug() << lib.errorString();
          }
 
          if (lib.isLoaded()) {
            qDebug() << "success";
 
            // Resolves symbol to
            // void the_function_name()
            typedef int (*FunctionPrototype)();
            auto function1 = (FunctionPrototype)lib.resolve("MUX_Version");
 
 
            // if null means the symbol was not loaded
            if (function1) function1();
          }
        }
 
    MainWindow w;
    w.show();
    return a.exec();
}

What can I do?
What am I doing wrong?

I already looked into several forum entries but did not find the working answer.

Thanks in advance
Tim