QT missing dll after deploy

Question

I've copied all of the dlls from QT that were required, and my application works fine on my Windows server machine.

However when trying to run it on a Windows 7 box i get the following message:

This application failed to start because it could not find or load he Qt platform plugin "windows".

Reinstallning the application may fix this problem.

Any ideas what I'm missing here?

Answer 1

I'd scratched my head over this some time ago. It turned out that this was caused not by missing qwindows.dll, but rather one of libEGL.dll or libGLESv2.dll. This was tricky, because dependency walker does not show those libs as direct dependencies.

If you want to test on your dev machine, whether your app has all required libs, fire up console issue SET PATH=, cd to your app directory and run it.

This is complete list of dlls that my app is using (Qt 5.2 / QtQuick app only, rest is C++). QtQuick is nice but the size of Qt dependencies is a bit scary:

icu*.dll - depending on whether you've compiled with ICU libEGL.dll libGLESv2.dll Qt5Core.dll Qt5Gui.dll Qt5Network.dll Qt5Qml.dll Qt5Quick.dll Qt5Widgets.dll