Qt Platform Plugin Windows
Edit: Some people started to mark my question as a duplicate. Do not forget that many similar questions existed when I asked this one (see e.g. The list below). However, none of these answers solved my problem. After a long search I found a comment which had been ignored by all users pointing to the missing lib. Now, many months later, the comment has been changed to an answer. However, when I answered this question by msyself I intended to help other people by directly providing the solution.
This should not be forgotten and so far my answer helped a lot of people. Therefore my question is definitely not a duplicate.
Basically, since the application was developed using Qt, the dependencies will be only Qt dll and some few dll connected to the compiler used. To detect which dll are required by your executable there is an useful tool called Dependency Walker.
By the way: The accepted answer within the provided link on top does not solve the problem! Yes, i used the search: However, in my case the problem still persists. I am using Qt 5.1.1 with Visual Studio 2012 and developed my Application on Windows 7 with Qt Creator 2.8.1. Application is compiled in 'Release'-mode and can be executed if directly started with Qt Creator. However, when starting from the 'release'-Folder, i get the following message: This application failed to start because it could not find or load the Qt platform plugin 'windows'. Available platform plugins are: minimal, offscreen, windows. Folder structure looks like this: release + gui.exe + icudt51.dll + icuin51.dll + icuuc51.dll + libGLESv2.dll + Qt5Core.dll + Qt5Gui.dll + Qt5Widgets.dll + platforms Platforms is the folder directly copied from Qt Qt5.1.1 5.1.1 msvc2012 plugins platforms including e.g.
Does not matter if I rename it to 'platform' as some other users did. Qt is still not finding the 'platform plugin windows', where is my mistake? I created a platforms directory next to my exe location and put qwindows.dll inside, but I still received the 'Failed to load platform plugin 'windows'. Available platforms are: windows' error. I had copied qwindows.dll from C: Qt Qt5.1.1 Tools QtCreator bin plugins platforms, which is not the right location. Avast internet security final licence avastlic 2038 game. I looked at the debug log from running in Qt Creator and found that my app was looking in C: Qt Qt5.1.1 5.1.1 mingw48_32 plugins platforms when it ran in the debugger.
When I copied from C: Qt Qt5.1.1 5.1.1 mingw48_32 plugins platforms, everything worked fine. I found an unexpected but intuitive fix.
If you copy and paste the qwindows.dll, found in the bin of whichever compiler you used to release your application, into a folder named 'platforms' you can then move that folder into the same directory as your application and like magic it works. Also another helpful tip, Qt comes with platform console applications that will add all dependencies (including ones such as qwindows.dll and libEGL.dll) into the folder of your deployed executable. The application for windows is called windeployqt and the documentation can be found here.
This application saved me so much time and it's really the proper way to deploy your executable, so as not to miss anything. Most of these answers contain good (correct) info, but in my case, there was still something missing. My app is built as a library (dll) and called by a non-Qt application. I used windeployqt.exe to set up the Qt dlls, platforms, plugins, etc. In the install directory, but it still couldn't find the platform. After some experimentation, I realized the application's working directory was set to a different folder.