If you come across the error “This application failed to start because no Qt…”, Qt must be acting up and you should replace Qt files. Furthermore, you could perform a clean boot, uninstall and reinstall the affected app, run SFC and DISM scans, remove recent Windows updates, etc. Spare some time to take a look at this article to tackle the error and put your application to good use.
The Main Questions
What is Qt?
For your information, Qt is a cross-platform software made for creating graphical interfaces as well as cross-platform applications in Windows, Linus, macOS, and Android.
How do I install Qt?
- Step 1: Go to the Qt website and create an account
- Step 2: Click Downloads in the left panel, select your preferred version and choose Downloads to get the Qt Installer.
- Step 3: When the download concludes, press Windows + E to open Quick access, open Downloads and run the Qt Installer.
- Step 4: Sign in using your Qt account then keep hitting Next. Proceed to choose between Help us to improve by enabling sending pseudonymous usage statistics in Qt Creator and Disable sending pseudonymous usage statistics in Qt Creator then hit Next. You then need to choose the folder where Qt will be installed and the version of Qt that you desire. Afterward, check the Associate common file types with Qt Creator and click Next
- Step 5: Select the components you want to install and choose Next. Check I have read and agree to the terms contained in the license agreements then hit Next. In the case that everything is up to your liking, click Next and pick Install.
Which versions of Windows does Qt support?
Qt 6.4 supports Windows 10 (1809 or later) and Windows on ARM while Qt 6.2 supports Windows 11. Older versions of Windows are not supported by Qt.
Reasons Why Qt Won’t Work
Overall, Windows applications could run into various errors in use but regarding “This application failed to start because no Qt…”, you should consider the following suspects:
- Qt
- Third-party apps
- Corrupted system files
- Windows updates
Dealing With Qt Issues: Guidelines
Replace Qt Files
Note: For ease of convenience, we use Python for the solution. If you experience the error “This application failed to start because no Qt…” while using another app, go the folder of that app.
- Step 1: Press Windows + E to open File Explorer, hit This PC and search for pyqt5_tools using the search box on the top-right.
- Step 2: Right-click the pyqt5_tools folder then pick Open folder location.
- Step 3: Navigate to PyQt5 > Qt > plugins, right-click the platforms folder and pick Copy.
- Step 4: Right-click the platforms folder and choose Copy
- Step 5: Go back to the site-packages folder then navigate to pyqt5_tools > Qt > bin. Next, right-click on the empty space in the bin folder, pick Paste and hit Replace the files in the destination message. Last but not least, launch the app then determine whether the issue persists.
Perform A Clean Boot
- Step 1: Press Windows key, type msconfig and press Enter to open System Configuration.
- Step 2: Go to Services tab, select Hide all Microsoft services and choose Disable all.
- Step 3: Go to the Startup tab, hit Open Task Manager and disable everything in your sight.
- Step 4: Close Task Manager, return to System Configuration and hit OK.
- Step 5: Restart your computer.
If your app launches as expected following clean boot, feel free to conclude that one of the third-party apps is the root of the trouble. To get rid of the error for good, you should uninstall recently installed apps. Finally, you could change back to normal startup by following the steps down below:
- Step 1: Press Windows key, type msconfig and press Enter to open System Configuration.
- Step 2: Click Normal Startup on General tab of System Configuration then click OK.
- Step 3: Restart your computer.
Uninstall And Reinstall The Affected App
- Step 1: Press Windows + I to open Settings.
- Step 2: Pick Apps, search for the affected app in Apps & features then click it.
- Step 3: Hit Uninstall, follow onscreen instructions and restart your computer.
- Step 4: When the screen comes back on, reinstall the app, launch it and see how things turn out.
Run SFC And DISM Scans
- Step 1: Press Windows key, type cmd and hit Run as administrator to open Command Prompt with administrative privileges.
- Step 2: In Command Prompt (Admin), type sfc /scannow and press Enter to run the SFC scan.
- Step 3: The moment the SFC scan completes, type the following commands in Command Prompt (Admin) and press Enter after you finish each to run the DISM scan:
- DISM /Online /Cleanup-Image /ScanHealth
- DISM /Online /Cleanup-Image /CheckHealth
- DISM /Online /Cleanup-Image /RestoreHealth
- Step 4: Type exit then press Enter to close Command Prompt.
- Step 5: Restart your computer.
Remove Recent Windows Updates
- Step 1: Press Windows + I to open Settings, choose Update & Security and select View update history in Windows Update.
- Step 2: Hit Uninstall updates, right-click recent updates and pick Uninstall.
- Step 3: Restart your computer as soon as the uninstallation wraps up.

Fredrik is one of Europe’s most experienced investors and one of the most trusted advisors to the Creandum portfolio companies.
At Creandum, Fredrik is an early backer of several companies that have grown to dominate their respective markets, among others Spotify, KRY / LIVI, depop and Kahoot!. Focusing on B2B- and B2C companies disrupting large markets, often with marketplace models, he also leads or has led Creandum’s work with Virta Health, Shapr3D, Xeneta, Careship, Soundtrack Your Brand, Cint (sold to Nordic Capital), Videoplaza (Ooyala), 13th Lab (Facebook) and Autobutler (PSA Group).