Qt Creator nor standalone installation works on Windows 8 Pro

[wilhelmsen]

Hi,

I tried to deploy my application on a Windows 8 laptop. The application was developed on Windows 7 with Qt5 and MinGW and was working fine both from Creator and standalone. When trying to execute my .exe under Windows 8, I get the error

bq. This application failed to start because it could not find or load the Qt platfor plugin "windows". Available platform plugins are: minimal, offscreen. Reinstalling the application may fix this problem.

Now, I have read MANY places that I just need to add the libEGL.dll, but this is appearently for people using the Visual Studio compiler, not MinGW.

I then tried installing the Qt Creator and SDK, just to see if I could at least run an empty project. I created a empty GUI project, and when starting the application from Creator I got the same error as before. So, Qt is not working at all!

When running dependancy walker, I got these DLL's missing:

API-MS-WIN-CORE-KERNEL32-PRIVATE-L1-1-1.DLL
API-MS-WIN-CORE-PRIVATEPROFILE-L1-1-1.DLL
API-MS-WIN-SERVICE-PRIVATE-L1-1-1.DLL

I did not find these dll's under my windows installation, so I downloaded these from external sources and added them to my executables folder. Still, same error. After roaming around for answers, I added qwindows.dll, qminimal.dll and qoffscreen.dll to my <exe-dir>\plugins, not working, moved them to <exe-dir>\platforms, still not working.

Since even Creator cannot give me anything except the ability to compile and build my application, does this have something to do with my Windows innstallation? FYI, I tried this on two different computers running Windows 8 Pro.

Please help me find a solution to this!

[Jeroentjehome]

Hi,
Also from your Qt library bin folder copy the /platforms/windows.dll file!!
Was my mistake as well, check out the deployment docs!!

[wilhelmsen]

[quote author="Jeroentje@home" date="1393248369"]Hi,
Also from your Qt library bin folder copy the /platforms/windows.dll file!!
Was my mistake as well, check out the deployment docs!![/quote]
Thank you!
Under my C:\Qt\Qt5.2.0-mingw\5.2.0\mingw48_32\bin there are no windows.dll file. Where can I find this dll exactly?
Also, under C:\Qt\Qt5.2.0-mingw\5.2.0\mingw48_32\plugins\platforms there are only these files:
qminimal.dll
qminimald.dll
qoffscreen.dll
qoffscreend.dll
qwindows.dll
qwindowsd.dll

[vezprog]

you want the qwindows.dll for deployment in release,

If you go into your bin folder in your Qt5 installation directory, there are some dll's that are required as well when deploying Qt5.

My development system is using Qt5.2 / VS2010 compiler (for xp compatibility) on windows 7/8

OS Specific dlls:
D3DCompiler_43.dll
icudt51.dll
icuin51.dll
icuuc51.dll
libEGL.dll
libGLESv2.dll

Qt specific modules (depends on what your application requires)
Qt5Core.dll
Qt5Gui.dll
Qt5Network.dll
Qt5Widgets.dll

Qt specific image plugins:
/imageformats/qgif.dll
/imageformats/qico.dll
/imageformats/qjpeg.dll
/imageformats/qmng.dll
/imageformats/qsvg.dll
/imageformats/qtga.dll
/imageformats/qtiff.dll
/imageformats/qwbmp.dll

Qt specific platforms plugins:
/platforms/qminimal.dll
/platforms/qoffscreen.dll
/platforms/qwindows.dll

[wilhelmsen]

Well, I have all those (except the VS specific ones), but still the error

bq. This application failed to start because it could not find or load the Qt platfor plugin “windows”. Available platform plugins are: minimal, offscreen. Reinstalling the application may fix this problem.

[SGaist]

Hi,

Have a look at JKSH's excellent wiki "entry":http://qt-project.org/wiki/Deploy_an_Application_on_Windows about that

For more details you can also go to the "Windows Deployment Guide":http://qt-project.org/doc/qt-5.0/qtdoc/deployment-windows.html

[wilhelmsen]

Been to both (love JKSH's post) . But the thing is, it works on Windows 7! The error message suggests I should only need to add qwindows.dll, which I have. Doesn't anyone know what the error message is supposed to show me besides going through every single dll there is?

[wilhelmsen]

[quote author="SGaist" date="1393257866"]Hi,

Have a look at JKSH's excellent wiki "entry":http://qt-project.org/wiki/Deploy_an_Application_on_Windows about that

For more details you can also go to the "Windows Deployment Guide":http://qt-project.org/doc/qt-5.0/qtdoc/deployment-windows.html[/quote]
Also, if you have a look at my question, I stated that it doesn't even work from Qt Creator

EDIT: Maybe I should have posted the question as "Qt Creator wont run applications on Windows 8" ?

[SGaist]

What puzzles me is that you have the other plugins listed.

Did you run Dependency Walker on qwindows.dll or your application ?

[wilhelmsen]

I did not on the qwindows.dll, but I did on the app and added the dlls posted in the question. I shall try walker on qwindows.dll in a couple of hours. Thank you guys for your endless efforts!

[wilhelmsen]

Now this is a bit troubling. I came home from work and testing my application at my Windows 8.1 Pro computer, and everything works fine! I have struggled with this for two days now. Is there an inconsistency between 8.1 pro and 8.0 pro with regards to Qt?

All the tools are the exact same versions. Glad I finally figured out that I was at least doing what you guys told me to to make it work.

[SGaist]

I can't really say. Apple has done some subtle internal modification for Mavericks that also broke some things so there might be something fishy between Windows 8 and 8.1 or maybe some anti-virus interaction

[JKSH]

Hi,

[quote]I then tried installing the Qt Creator and SDK, just to see if I could at least run an empty project. I created a empty GUI project, and when starting the application from Creator I got the same error as before. So, Qt is not working at all![/quote]That sounds like an issue with your laptop, not with missing DLLs.

Try to get an app to run correctly from Qt Creator on that laptop first. Until you succeed in that, it's highly unlikely that any deployed application will work.

Which version of Qt did you install on this laptop? (Is it Qt 5.2.1 for Windows 32-bit (MinGW 4.8, OpenGL, 634 MB)?)

What graphics card does it have?

[quote]I tried this on two different computers running Windows 8 Pro.[/quote]Are they the same brand + model of computers?

[quote]When running dependancy walker, I got these DLL’s missing:

API-MS-WIN-CORE-KERNEL32-PRIVATE-L1-1-1.DLL
API-MS-WIN-CORE-PRIVATEPROFILE-L1-1-1.DLL
API-MS-WIN-SERVICE-PRIVATE-L1-1-1.DLL

I did not find these dll’s under my windows installation, so I downloaded these from external sources and added them to my executables folder.[/quote]These are false positives. Dependency Walker will always complain that these DLLs are missing, no matter what program you examine (even official Microsoft ones). Ignore the message, and delete these DLLs from your deployment folder. The only DLLs you need can all be found in your Qt installation (unless you link to 3rd-party libraries).

Also, it's generally a bad idea to download DLLs from unofficial Internet sources. You never know if they've been tampered with.

[quote]Now, I have read MANY places that I just need to add the libEGL.dll, but this is appearently for people using the Visual Studio compiler, not MinGW.[/quote]Actually, this is for people using ANGLE, not OpenGL.

[wilhelmsen]

[quote]Hi,
That sounds like an issue with your laptop, not with missing DLLs.
Try to get an app to run correctly from Qt Creator on that laptop first. Until you succeed in that, it's highly unlikely that any deployed application will work.

Which version of Qt did you install on this laptop? (Is it Qt 5.2.1 for Windows 32-bit (MinGW 4.8, OpenGL, 634 MB)?)

What graphics card does it have?[/quote]

Qt 5.2.0, MinGW 4.8 32bit

Unsure about graphic cards

[quote]Are they the same brand + model of computers?[/quote]
No, one was a surface 10", the other a regular HP 15" laptop.

[quote]These are false positives. Dependency Walker will always complain that these DLLs are missing, no matter what program you examine (even official Microsoft ones). Ignore the message, and delete these DLLs from your deployment folder. The only DLLs you need can all be found in your Qt installation (unless you link to 3rd-party libraries).

Also, it's generally a bad idea to download DLLs from unofficial Internet sources. You never know if they've been tampered with.[/quote]
Thank you. Fortunately I did not need the downloaded DLL's anyway on the working computer.

[quote]Actually, this is for people using ANGLE, not OpenGL.[/quote]
Okay. I just saw that everyone else having this problem was using ANGLE and Visual Studio :)

Sorry for not having more details about hardware, but I am not in control of those laptops anymore. A new one is to be bought, so lets hope the error doesn't occur there as well. Will notify you about success or failure.

[JKSH]

[quote author="wilhelmsen" date="1393314366"][quote]Hi,
That sounds like an issue with your laptop, not with missing DLLs.
Try to get an app to run correctly from Qt Creator on that laptop first. Until you succeed in that, it's highly unlikely that any deployed application will work.

Which version of Qt did you install on this laptop? (Is it Qt 5.2.1 for Windows 32-bit (MinGW 4.8, OpenGL, 634 MB)?)

What graphics card does it have?[/quote]

Qt 5.2.0, MinGW 4.8 32bit

Unsure about graphic cards

[quote]Are they the same brand + model of computers?[/quote]
No, one was a surface 10", the other a regular HP 15" laptop.[/quote]The reason I asked about your graphics card and computer model is because parts of Qt require OpenGL 2.0 or higher. By default, Windows only ships with OpenGL 1.1, which will cause errors if you try to run a Qt application that needs OpenGL (although I don't know what the exact symptoms are).

To overcome this, Qt provides an ANGLE option, to use DirectX instead of OpenGL.