@PerssonBrown said in CMake can NOT find Vulkan when building: Here are my questions: What is Vulkan? It is a library for displaying graphics, much like OpenGL, DirectX or Metal. Do all Widget Applications need Vulkan? No, you can safely ignore this warning. When Vulkan is not present, Qt will use other libraries to draw stuff. How to fix this missing warning? On Windows I'm not sure if you can fix it, but you can ignore it.

You should give more details about the device and Qt backend you are using.

Simple Method.. From the desktop, right click the Computer icon. Choose Properties from the context menu. Click the Advanced system settings link. list item Click Environment Variables. In the section System Variables, find the PATH environment variable and select it. Click Edit. If the PATH environment variable does not exist, click New. In the Edit System Variable (or New System Variable) window, specify the value of the PATH environment variable example(C:\Qt\Mingw32\bin). Click OK. Close all remaining windows by clicking OK

Hi, 32bit Windows 7 Home Edition. Anyway maybe I found a workaround. In case an error occurs when trying to play the movie, there is a maximum number of retries... I have done this because my suspect is that, due to the CF-19 "poor" performances, the libraries aren't (fully) loaded when the movie is played. I will keep you up to date whether this is or this is not THE solution, for anyone else's benefit. Thanks to everybody!