TheITGuy, thanks for your solution.
I made the mistake to put the setup.exe with its parameters in the 'Install File' field.
Now I have put the parameters in the "Parameters" field and it works (with the msp file).
Install File: {PackageShare}\Installers\Office2016\setup.exe
Parameters: /adminfile "{PackageShare}\Installers\Office2016\Office2016ProPlus32.MSP"
Result Command: "{PackageShare}\Installers\Office2016\setup.exe" /adminfile "{PackageShare}\Installers\Office2016\Office2016ProPlus32.MSP"
So the problem is solved.