App released with windeployqt not showing UI

[Fausto01]

I have released a windows app using windeployqt. It works everywhere except on one PC. On that PC (Windows 10 Pro) the app runs (I can see it from the Task Manager) but UI is not shown.
These are the steps I do to release the app:

rmdir /S /Q install
mkdir install
copy "build\Desktop_Qt_5_14_2_MinGW_64_bit\Release\release\MyApp.exe" install
C:\Qt\5.14.2\mingw73_64\bin\windeployqt.exe --qmldir qml install\MyApp.exe
copy "C:\Qt\5.14.2\mingw73_64\bin\libgcc_s_seh-1.dll" install
copy "C:\Qt\5.14.2\mingw73_64\bin\libstdc++-6.dll" install
copy "C:\Qt\5.14.2\mingw73_64\bin\libwinpthread-1.dll" install
pause

Am I missing something? Thank you

[jsulm]

@Fausto01 Did you try to start the app from a terminal to see whether there are any warnings/errors?
You can also set QT_DEBUG_PLUGINS in terminal before starting your app to see whether and what problems you have with the plug-ins (https://doc.qt.io/qt-6/deployment-plugins.html).

[Fausto01]

I tried to start the app from terminal but the console didn't print anything. I'll try to set QT_DEBUG_PLUGINS=1 and start the app from terminal as soon as I can. The strange thing is that on another PC with Windows 10 Pro works like a charm.

[jsulm]

@Fausto01 I would also check the anti-virus software - could be that it blocks the app.

[Fausto01]

@jsulm I thought the same thing but no antivirus is installed on that machine. The app is running because I can see it from the Task Manager, but the UI doesn't want to come up.

[J.Hilk]

@Fausto01 is it maybe a VM? thats always not working quite right

also make sure that PC has the up to date graphics drivers installed

[Fausto01]

@J-Hilk It's a native Windows 10 Pro, I'll try to update graphics drivers. Unfortunately I don't have the PC right now. I'll keep you updated. If you have other suggestions I will try

[Fausto01]

I've tried to set QT_DEBUG_PLUGINS=1 and run the application from terminal (even started as admin) but nothing has changed. I also checked the drivers and it is all updated. Any hint?

[JonB]

@Fausto01
You should have received a lot of diagnostic output in the terminal... ?

[Fausto01]

@JonB I've also tried to set CONFIG+=console in the .pro but the only thing that is shown on the terminal is "QML debugging is enabled. Only use this in a safe environment.". Than the app remains alive but with no GUI

[Fausto01]

Update: I've tried to create a file just after the creation of QApplication but the file was not created. Seems that the application stucks in the creation of QApplication, is it possible? I think I miss some dll but I don't know which one.

[Fausto01]

Guys please I'm stucked and I need to resolve asap, has someone something to try? Thak you

[hskoglund]

Hi, the failing PC, is it a portable PC with Intel integrated graphics adapter?

[SGaist]

Hi,

One thing that is strange is your qmldir option. It should be pointed to your application sources where you store your QML files so that their dependencies are all deployed.

It looks a bit unrelated since you have your application showing on some machines but still, it would be better to fix it.

[Fausto01]

@hskoglund Yes it has no dedicated graphic board.

[Fausto01]

@SGaist The batch file with the commands for releasing the app is at the same level of the qml directory, something like this:

└── Project/
    ├── release.bat
    ├── qml/
    │   └── main.qml
    └── src/
        └── main.cpp

[hskoglund]

I had same problem using QML on a Windows 10 portable PC with an integrated Intel graphics adapter. The solution that worked for me was to upgrade the graphics driver to the latest version from Intel. maybe it will help you also.

[Fausto01]

@hskoglund Seems that it's already the newest version (from Windows Update)

[hskoglund]

Windows Update didn't work for me, I had to go to the Intel website and fetch the driver there.

[kkoehne]

@Fausto01 said in App released with windeployqt not showing UI:

I've tried to set QT_DEBUG_PLUGINS=1 and run the application from terminal (even started as admin) but nothing has changed. I also checked the drivers and it is all updated. Any hint?

Windows GUI apps do not have a console by default, and therefore also do not write debug information to the console. Instead, it goes to the central 'debug buffer'. You can see the output of the buffer by a) launching your app in an IDE like Qt Creator, or b) run the standalone dbgview.exe.

(Caveat: Only one client should listen to the debug buffer at any given time on the whole machine.)

Try this, and setting QT_DEBUG_PLUGINS environment variable should really print you a lot of information.