Quote Originally Posted by JanW View Post
QQmlApplicationEngine failed to load component
qrc:/qml/main.qml:16 plugin cannot be loaded for module "ArcGIS.Runtime": Cannot load library C:\Qt\5.7\msvc2013_64\qml\ArcGIS\Runtime.10.26\Arc GISRuntimePlugind.dll: The specified module could not be found. (the dll is there at that location)
You could try setting the environment variable QT_DEBUG_PLUGINS to 1 and see if this gives you more hints in the application's log output.

Quote Originally Posted by JanW View Post
According to their install instructions (https://developers.arcgis.com/qt/qml...on-windows.htm) they use the vs compiler in qt creator to compile the projects, so i guess it's not a compiler compatibility issue.
Since there is no such thing as "the" vs compiler as they are basically all incompatible with each other, check that it is exactly the same version, bit-ness, etc.

Quote Originally Posted by JanW View Post
What can be the difference between the qt creator project and the vs project? Are there some input paths that are different or so? Anybody an idea?
You could check the environment in QtCreator's project/run settings so see if your VS setup is missing any of these are has different values.

Cheers,
_