No Qt platform plugin could be initialized

hskoglund

Hi it's complaining about the C:\Qt5\Tools\QtCreator\bin\plugins\platforms\qwindows.dll file, that it's a not a valid .dll. Do you have any 3rd party antivirus program like Avast installed?
Also check the size and date of that file, mine looks like this:

C:\Qt\Tools\QtCreator\bin\plugins\platforms>dir qwindows.dll
 Volume in drive C has no label.
 Volume Serial Number is 2468-E241

 Directory of C:\Qt\Tools\QtCreator\bin\plugins\platforms

2022-06-02  16:18           802 704 qwindows.dll
               1 File(s)        802 704 bytes
               0 Dir(s)  70 671 708 160 bytes free

ham13

Mine reads:

06/02/2022 10:18 AM 802,704 qwindows.dll
1 File(s) 802,704 bytes
0 Dir(s) 273,429,200,896 bytes free

C:\Qt5\Tools\QtCreator\bin\plugins\platforms>

Properties:
6/2/22 - Version 6.3.1

Yes I'm running Trendmicro antivirus with Windows Defender.

Thanks

JonB

@ham13

qt.core.plugin.loader: QLibraryPrivate::loadPlugin failed on "C:/Qt5/Tools/QtCreator/bin/plugins/platforms/qwindows.dll" :
"Cannot load library C:\Qt5\Tools\QtCreator\bin\plugins\platforms\qwindows.dll:
The specified procedure could not be found."

It's not actually complaining that it cannot load the DLL per se, it's saying that it could not find the exported procedure it was asking for/expecting to find. Unfortunately we don't know which procedure name. Not that it helps much solve why/what to do.

hskoglund

If you disable TrendMicro do you get the same error?

Edit: forgot to say, it could be you're missing some stuff from Microsoft that qwindows.dll needs to load ok, I'm thinking about the Visual C++ redistrubuable files (early versions of Windows 10 do not have them). Go here to install and choose the X64 flavor.

ham13

Same error with antivirus (TrendMicro) off or on. Installed Visual C++ redistributable 64 bit. No change. I get same error on both Qt6 and qt5. I have installedQt5 in \Qt5. Maybe I should have installed it in C:?

Thanks

hskoglund

Hi, you could try launching Qt Creator without loading or requiring qwindows.dll, open a CMD window:
C:\Qt5\Tools\QtCreator\bin\qtcreator.exe -platform direct2d

If that fails: the problem could be some detritus from previous Qt versions that still remains. One way to test that is if you create a new user on your PC, log out and log in as that new user. Then try start Qt Creator on that desktop (if there's no icon to launch it you might have to navigate to the qtcreator.exe file manually).

*Edit": also a good test of Qt's health is to run qtdiag.exe from a CMD window. (There's usually 2 of them for a given Qt release, one in the mscv2019\bin subdirectory and one in Qt\Tools\QtCreator\bin so try running all 4 of them :-)

ham13

Ran C:\Qt5\Tools\QtCreator\bin\qtcreator.exe -platform direct2d. Got same error.
Tried new Windows user. No change.

Found qtdiag in Qt5\5.15.2\msvc2015-64\bin. Found QtAsistant, QtDesigner and QtLinguist in this directory and all three ran. Unfortunately Result below QtCreator was not there. Maybe these are leftover from a previous install? the do not show up in "Programs and features". How should I clean them out?

qtdiag result:

C:\Qt5\5.15.2\msvc2015_64\bin>qtdiag.exe
Failed to load vulkan-1: Cannot load library vulkan-1: The specified module could not be found.
initInstance: No Vulkan library available
Failed to create platform Vulkan instance
Failed to load vulkan-1: Cannot load library vulkan-1: The specified module could not be found.
initInstance: No Vulkan library available
Failed to create platform Vulkan instance
Vulkan instance is not valid
Qt 5.15.2 (x86_64-little_endian-llp64 shared (dynamic) release build; by MSVC 2015) on "windows"
OS: Windows 8.1 Version 6.3 (Build 9600) [winnt version 6.3.9600]

Architecture: x86_64; features: SSE2 SSE3 SSSE3 SSE4.1 SSE4.2 AVX

Environment:

Features: QT_NO_EXCEPTIONS

Library info:
PrefixPath: C:\Qt5\5.15.2\msvc2015_64
DocumentationPath: C:\Qt5\Docs\Qt-5.15.2
HeadersPath: C:\Qt5\5.15.2\msvc2015_64\include
LibrariesPath: C:\Qt5\5.15.2\msvc2015_64\lib
LibraryExecutablesPath: C:\Qt5\5.15.2\msvc2015_64\bin
BinariesPath: C:\Qt5\5.15.2\msvc2015_64\bin
PluginsPath: C:\Qt5\5.15.2\msvc2015_64\plugins
ImportsPath: C:\Qt5\5.15.2\msvc2015_64\imports
Qml2ImportsPath: C:\Qt5\5.15.2\msvc2015_64\qml
ArchDataPath: C:\Qt5\5.15.2\msvc2015_64
DataPath: C:\Qt5\5.15.2\msvc2015_64
TranslationsPath: C:\Qt5\5.15.2\msvc2015_64\translations
ExamplesPath: C:\Qt5\Examples\Qt-5.15.2
TestsPath: C:\Qt5\5.15.2\msvc2015_64\tests
SettingsPath:

Standard paths [... denote writable entry]:
DesktopLocation: "Desktop" C:\Users\Marty\Desktop
DocumentsLocation: "Documents" C:\Users\Marty\Documents
FontsLocation: "Fonts" C:\WINDOWS\Fonts
ApplicationsLocation: "Applications" C:\Users\Marty\AppData\Roaming\Microsoft\Windows\Start Menu\Programs
MusicLocation: "Music" C:\Users\Marty\Music
MoviesLocation: "Movies" C:\Users\Marty\Videos
PicturesLocation: "Pictures" C:\Users\Marty\Pictures
TempLocation: "Temporary Directory" C:\Users\Marty\AppData\Local\Temp
HomeLocation: "Home" C:\Users\Marty
AppLocalDataLocation: "Application Data" C:\Users\Marty\AppData\Local\QtProject\qtdiag C:\ProgramData\QtProject\qtdiag C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data C:\Qt5\5.15.2\msvc2015_64\bin\data\QtProject\qtdiag
CacheLocation: "Cache" C:\Users\Marty\AppData\Local\QtProject\qtdiag\cache
GenericDataLocation: "Shared Data" C:\Users\Marty\AppData\Local C:\ProgramData C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data
RuntimeLocation: "Runtime" C:\Users\Marty
ConfigLocation: "Configuration" C:\Users\Marty\AppData\Local\QtProject\qtdiag C:\ProgramData\QtProject\qtdiag C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data C:\Qt5\5.15.2\msvc2015_64\bin\data\QtProject\qtdiag
DownloadLocation: "Download" C:\Users\Marty\Downloads
GenericCacheLocation: "Shared Cache" C:\Users\Marty\AppData\Local\cache
GenericConfigLocation: "Shared Configuration" C:\Users\Marty\AppData\Local C:\ProgramData C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data
AppDataLocation: "Application Data" C:\Users\Marty\AppData\Roaming\QtProject\qtdiag C:\ProgramData\QtProject\qtdiag C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data C:\Qt5\5.15.2\msvc2015_64\bin\data\QtProject\qtdiag
AppConfigLocation: "Application Configuration" C:\Users\Marty\AppData\Local\QtProject\qtdiag C:\ProgramData\QtProject\qtdiag C:\Qt5\5.15.2\msvc2015_64\bin C:\Qt5\5.15.2\msvc2015_64\bin\data C:\Qt5\5.15.2\msvc2015_64\bin\data\QtProject\qtdiag

File selectors (increasing order of precedence):
en_US windows winnt

Network:

SSL is not supported.

Platform capabilities: ThreadedPixmaps OpenGL ThreadedOpenGL WindowMasks MultipleWindows ForeignWindows NonFullScreenWindows NativeWidgets WindowManagement RasterGLSurface AllGLFunctionsQueryable

Style hints:
mouseDoubleClickInterval: 500
mousePressAndHoldInterval: 800
startDragDistance: 10
startDragTime: 500
startDragVelocity: 0
keyboardInputInterval: 400
keyboardAutoRepeatRate: 32
cursorFlashTime: 1060
showIsFullScreen: 0
showIsMaximized: 0
passwordMaskDelay: 0
passwordMaskCharacter: U+25CF
fontSmoothingGamma: 1.2
useRtlExtensions: 0
setFocusOnTouchRelease: 0
tabFocusBehavior: Qt::TabFocusAllControls
singleClickActivation: 0

Additional style hints (QPlatformIntegration):
ReplayMousePressOutsidePopup: 1

Theme:
Platforms requested : windows
available : snap,flatpak,xdgdesktopportal
Styles requested : WindowsVista,Windows
available : windowsvista,Windows,Fusion
System font : "MS Shell Dlg 2" 8
Native file dialog

Fonts:
General font : "MS Shell Dlg 2" 8
Fixed font : "Courier New" 9
Title font : "MS Shell Dlg 2" 8
Smallest font: "MS Shell Dlg 2" 8

Palette:
QPalette::WindowText: #ff000000
QPalette::Button: #fff0f0f0
QPalette::Light: #ffffffff
QPalette::Midlight: #ffe3e3e3
QPalette::Dark: #ffa0a0a0
QPalette::Mid: #ffa0a0a0
QPalette::Text: #ff000000
QPalette::BrightText: #ffffffff
QPalette::ButtonText: #ff000000
QPalette::Base: #ffffffff
QPalette::Window: #fff0f0f0
QPalette::Shadow: #ff696969
QPalette::Highlight: #ff3399ff
QPalette::HighlightedText: #ffffffff
QPalette::Link: #ff0000ff
QPalette::LinkVisited: #ffff00ff
QPalette::AlternateBase: #ffe9e7e3
QPalette::NoRole: #ff000000
QPalette::ToolTipBase: #ffffffdc
QPalette::ToolTipText: #ff000000
QPalette::PlaceholderText: #80000000

Screens: 1, High DPI scaling: inactive

0 "\.\DISPLAY1" Depth: 32 Primary: yes

Manufacturer:
Model:
Serial number:
Geometry: 1280x1024+0+0 Available: 1280x984+0+0
Physical size: 376x301 mm Refresh: 60 Hz Power state: 0
Physical DPI: 86.4681,86.4106 Logical DPI: 96,96 Subpixel_RGB
DevicePixelRatio: 1 Pixel density: 1
Primary orientation: 2 Orientation: 2 Native orientation: 0 OrientationUpdateMask: 0

Dynamic GL LibGL Vendor: Intel
Renderer: Intel(R) HD Graphics 2500
Version: 4.0.0 - Build 10.18.10.4276
Shading language: 4.00 - Build 10.18.10.4276
Format: Version: 4.0 Profile: 2 Swap behavior: 2 Buffer size (RGBA): 8,8,8,8 Depth buffer: 24 Stencil buffer: 8
Profile: None (QOpenGLFunctions_4_0), Core (QOpenGLFunctions_4_0_Core), Compatibility (QOpenGLFunctions_4_0_Compatibility)

Unable to create a Vulkan instance, error code is0

GPU #1:
Card name : Intel(R) HD Graphics
Driver Name : igdumdim64.dll
Driver Version : 10.18.10.4276
Vendor ID : 0x8086
Device ID : 0x0152
SubSys ID : 0x365317AA
Revision ID : 0x0009

Qt Rendering Hardware Interface supported backends:
OpenGL (with default QSurfaceFormat):
Min Texture Size: 1
Max Texture Size: 16384
Max Color Attachments: 8
Frames in Flight: 1
Uniform Buffer Alignment: 1
Supported MSAA sample counts: 1,2,4,8
Features:
- MultisampleTexture
v MultisampleRenderBuffer
- DebugMarkers
- Timestamps
v Instancing
- CustomInstanceStepRate
- PrimitiveRestart
v NonDynamicUniformBuffers
v NonFourAlignedEffectiveIndexBufferOffset
v NPOTTextureRepeat
- RedOrAlpha8IsRed
v ElementIndexUint
- Compute
v WideLines
v VertexShaderPointSize
v BaseVertex
- BaseInstance
v TriangleFanTopology
v ReadBackNonUniformBuffer
v ReadBackNonBaseMipLevel
Texture formats: RGBA8 BGRA8 R8 R16 RED_OR_ALPHA8 RGBA16F RGBA32F R16F R32F D16 D32F BC1 BC2 BC3 ETC2_RGB8 ETC2_RGB8A1 ETC2_RGBA8
Direct3D 11:
Min Texture Size: 1
Max Texture Size: 16384
Max Color Attachments: 8
Frames in Flight: 1
Uniform Buffer Alignment: 256
Supported MSAA sample counts: 1,2,4,8
Features:
v MultisampleTexture
v MultisampleRenderBuffer
v DebugMarkers
v Timestamps
v Instancing
v CustomInstanceStepRate
v PrimitiveRestart
- NonDynamicUniformBuffers
v NonFourAlignedEffectiveIndexBufferOffset
v NPOTTextureRepeat
v RedOrAlpha8IsRed
v ElementIndexUint
v Compute
- WideLines
- VertexShaderPointSize
v BaseVertex
v BaseInstance
- TriangleFanTopology
v ReadBackNonUniformBuffer
v ReadBackNonBaseMipLevel
Texture formats: RGBA8 BGRA8 R8 R16 RED_OR_ALPHA8 RGBA16F RGBA32F R16F R32F D16 D32F BC1 BC2 BC3 BC4 BC5 BC6H BC7

C:\Qt5\5.15.2\msvc2015_64\bin>

Thanks

hskoglund

Aha, I think the mystery is solved: qtdiag.exe says that you're in fact running Windows 8.1 and not Windows 10.
That explains why Qt 5.15.2 works except for Qt Creator 8.0.1 which is based on Qt 6.3.1. And Qt 6.3.1 does not run on Windows 8.1, it requires Windows 10 or 11.

To get a working Qt Creator, you can install a version of Qt Creator based on Qt 5. 15.2 from here: https://download.qt.io/snapshots/qtcreator_qt5/8.0/8.0.2/307/qt-creator-opensource-windows-x86_64-8.0.2_307.exe

ham13

OK. That was the problem. I downloaded and installed QtCreator 8.0.2 as you suggested. It loads and runs. I'll test it out with a project later. So it looks like I should continue with Qt 5.1 and not use Qt 6 unless I have a "real" Win 10 PC.

That also explains why I cannot use or upgrade MS OneDrive. There are no updates to Win 8.1 available. The PC just wants to see updates to Win 10.

My question it is true that the PC originally had Win 8 installed when we purchased it. Then MS came out with the free update to Win 10. We applied that update. We thought that it updated to Win 10 and I have added software based on that assumption. So which is it Win 8 or Win 10 or some
combination of both? Do I consider the OS to be Win 8 or Win 10?

Thank you for your patience and help! I never would have figured it out without you advice.

Thanks

JonB

@ham13 said in No Qt platform plugin could be initialized:

So which is it Win 8 or Win 10 or some
combination of both? Do I consider the OS to be Win 8 or Win 10?

Which one does it look like? If it didn't look any different at all after "upgrading" didn't that concern you? :)

How about: File Explorer, right-click on This PC, Properties. What does it tell you about your edition of Windows?

aankhka

Thank you all for your responses! I installed Qt and QtCreator using the Qt installer I downloaded from the Qt site. Installed both Qt5 and Qt6 separately

mobdro 2022