Failed to load platform plugin "windows".

MByte · wrote on 21 Oct 2012, 03:55

I built Qt5 64-bit with -platform win32-msvc2012 -opengl es2 -angle <path> on Windows 8.

Whenever I try to compile and run a Qt program, I get the following error:
@Failed to load platform plugin "windows".
Available platforms are:
minimal
windows@

If I build without ANGLE support, it works, but I need ANGLE to use OpenGL shaders.

It wasn't doing this before, but now it seems to happen no matter what. I've tried a number of qt5 repository pulls from different dates, different ANGLE repository pulls... even a fresh install of Windows and I still get the same error.

I traced a debug build, and it sees the platform plugin, but it seems that LoadLibrary is failing when trying to load it. Any ideas how to resolve this?

MByte · 14 Feb 2016, 14:22

Actually, I found the problem. ANGLE's libEGL.dll also needed to be in the path, not just libGLESv2.dll.

Thanks to toothrot in IRC for having me try Dependency Walker.

Macro · wrote on 23 Oct 2012, 14:20

Cool.. :)

MrNoway · wrote on 8 Jan 2013, 18:18

it's the "libEGLd.dll" not the "libEGL.dll"

but thanks, this was puzzling me.

napajejenunedk0 · wrote on 1 Feb 2013, 10:08

Which library depends on libEGL? libGLES or Qt5Widgets, Qt5Gui? Since, using Dependency Walker, neither my Qt 5 application's executable, nor the libraries it depends on, depend on libEGL. I presume it is loaded dynamically.

napajejenunedk0 · wrote on 9 Mar 2013, 19:47

I've found that it is qwindows.dll platform plugin that depends on libEGL.

d.mancic · wrote on 24 Apr 2013, 08:47

Hi people,

I have the same problem.

I copied .exe file in separate folder, along with many .dll files.
On the computer where I developed the application, everything works.

However, on the other computers there is still a message:

///////////////////////////////////////////////////////////////////////
Failed to load platform plugin "windows". Available platforms are:

(Press Retry...)
///////////////////////////////////////////////////////////////////////

I also included qwindowsd.dll.

Can someone help?

Thank you,

Dusan

goblincoding · wrote on 24 Apr 2013, 08:54

See "this thread":http://qt-project.org/forums/viewthread/27056/#122634 for a list of dll's and folder structure.

d.mancic · wrote on 24 Apr 2013, 09:06

It helped me! The problem was in folder structure.

Thank you very much!

Dusan

SGaist · wrote on 24 Apr 2013, 09:32

Hi,

Have a look at the "deployment":http://qt-project.org/doc/qt-5.0/qtdoc/deployment-windows.html documentation.

Did you put your platform plugin in the platform subdir ? (Not in the plugins subdir)

And are you sure you want do deploy the debug version (unless it's a typo)? The debug runtime from visual studio are not redistributable.

Hope it helps

d.mancic · wrote on 24 Apr 2013, 09:44

I solved that already (sent in previous email :)), but thanks anyway!

CarlStenquist · wrote on 19 Sept 2013, 15:22

THANK YOU MByte! I am using libGLESv2.dll and was having the exact same problem: The pop-up

..could not find or load the Qt platform plugin windows..

when trying to run the EXE-file. I could not resolve this until adding libEGL.dll to the same folder as my .EXE.
How is one supposed to figure this out?
This needs be explained somewhere - It took me 4 h. to find this!
Someone please add to QT documentation!
Carl Stenquist, Renesas

mphair · wrote on 21 Feb 2014, 11:58

I still cannot solve this issue. I've added qwindows.dll and libEGL.dll and any other dll I could find and I still get the same popup error.

CarlStenquist · wrote on 21 Feb 2014, 17:05

Look at what DLLs are loaded when you run the code in QT-Creator.
The DLLs must be for the sytem you are running, that is 32 OR 64 bit; the right version.
For my app, I needed qwindows.dll, qminimal.dll, qoffscreen.dll in a "platforms" directory under the executable.
But all such info seems missing in the QT documentation.
=Carl

JKSH · wrote on 21 Feb 2014, 23:55

[quote author="mphair" date="1392983929"]I still cannot solve this issue. I've added qwindows.dll and libEGL.dll and any other dll I could find and I still get the same popup error.[/quote]Hi,

Did you put them in the correct folders? See http://qt-project.org/wiki/Deploy_an_Application_on_Windows

CarlStenquist · wrote on 24 Feb 2014, 19:15

JKSH
How did you find that page - other than by through a search? I cannot see a link to it on the Wiki Home page. http://qt-project.org/wiki

Is the page so new that it is not linked to the main page yet?
=Carl

SGaist · wrote on 24 Feb 2014, 21:22

He wrote it :)

MaxteN · wrote on 9 Jun 2014, 16:24

Worked for me after I did the following:

include "$(QTDIR)\include\QtANGLE" to the project
include "libEGL.dll" in the .exe directory (libEGLd.dll if debug)
put "qwindows.dll" in "platforms\qwindows.dll"
bq. See this thread [qt-project.org] for a list of dll’s and folder structure.bq.

THANKS ALL!

Filip9322 · M MByte 21 Oct 2012, 04:16

@MByte https://www.youtube.com/watch?v=eHlDAT-haE0

Dave W · wrote on 18 Jun 2016, 21:02

None of these solutions works on a Win 8.0 machine. I'm trying to use Harbour with QT which has proven to be nothing but a complete waste of time and effort. Countless hours spent chasing BS issues that should never exist. I have the dll's in the folders described and it does not work! In my opinion, do not waste your time with Harbour and QT. I also hate C++ so QT is not for me. I'm going back to a real development environment, .NET!!!!!!