Why Can't My Qt Application Find the 'windows' Platform Plugin?

Application Startup Failure Due to Qt Platform Plugin Issue

When attempting to launch a Qt application on Windows, users may encounter the error: "Application failed to start because it could not find or load the QT platform plugin "windows"". This issue has been encountered by developers using Qt 5.2.0 on Windows 7 and Vista.

Troubleshooting Steps

• Verify Platform Plugin Path: Ensure that qwindows.dll is present in the .platforms/ directory within your application's directory. The path from the executable to qwindows.dll should be platforms/qwindows.dll.

• Add Library Path: If the previous step alone does not resolve the issue, add the following line at the beginning of your main() function:

  QCoreApplication::addLibraryPath("./");

• Ensure Redistributables: Verify that the correct Visual C redistributables are installed on the target machine. The required redistributables include:

  • VC Redist 2015 or 2013
  • VC Redist 2012
  • VC Redist 2010
• Check Dependency Walker Errors: If you encounter additional errors in Dependency Walker, such as "GetCurrentPackageId" or "BufferedPaintUnInit" errors, research and resolve those errors separately.

Additional Tips

• Make sure you have built Qt correctly with the "-platform win32-msvc2012" option.
• Double-check that the application is compiled as a 32-bit executable.
• Include qminimal.dll and qoffscreen.dll in the .platforms/ directory if necessary.
• As a last resort, reinstall the Qt libraries and platform plugins.

By following these troubleshooting steps, you can resolve the issue where the Qt platform plugin "windows" cannot be found or loaded, allowing your Qt application to start successfully on Windows.

The above is the detailed content of Why Can't My Qt Application Find the 'windows' Platform Plugin?. For more information, please follow other related articles on the PHP Chinese website!