Fix lỗi the dropbox installer failed to start

Have you recently run into the “Application failed to start because no Qt platform plugin could be initialized” error? QT is a cross-platform app that is used to generate graphical user interfaces. Even if QT support for Windows platforms is extensive, your system might display the error message when you try to open OneDrive, OBS Studio, Python, or even video games.

While this isn’t one of the common errors on Windows, you can still fix it using the tips below.

1. Change the QT Files Location

Sometimes, a simple trick such as changing the QT files location is enough to get rid of the error. Here’s how you can do it:

1. Launch File Explorer and open This PC.
2. Using the Search field, search for pyqt5_tools.
3. When Windows finishes the search, right-click the pyqt5_tools and head to Open folder location.
4. Head to PyQt5 > Qt > bin. Copy the platforms folder.
5. Make a new search for site-packages and open the folder.
6. There, paste the platforms folder.
7. Windows will warn you there’s already a folder with the same name. Click Replace the files in the destination.

2. Run an SFC Scan

There’s a chance Windows display the “Application failed because no QT platform plugin could be initialized” error due to corrupt system files. Fortunately, Windows has a built-in tool to help you fix the problem.

In the Start menu search bar, search for command prompt and select Run as administrator. Then, run the sfc /scannow command line. Windows will scan and automatically replace any corrupted system file.

If the System File Checker didn’t fix the problem, there are more built-in tools to repair corrupt Windows files.

3. Perform a Clean Boot

One of the installed third-party apps might be the reason why you get the “Application failed because no QT platform plugin could be initialized” error. To test it, perform a clean boot on Windows, which will force it to boot with a minimal list of programs and drivers.

If Windows stops displaying the error, it means something you've installed on your PC is causing the problem. Take a look at your installed apps, and remove any software that might be causing the problem. If you're unsure as to what might be doing it, slowly re-enable apps through the clean boot until the issue reappears.

4. Update the Malfunctioning App

An outdated version of the app you're trying to use might be the reason for the QT error. In this case, simply updating the app should solve the issue.

If you’ve downloaded the app from Microsoft Store, launch it and head to Library. There, you’ll see a list of available updates. You can update the apps individually, or click Get updates to update them all.

5. Reinstall the Troublesome App

As the error message hints, reinstalling the app might fix the problem. When reinstalling the app, make sure you get it from its official website, to avoid any future problems.

If you're having issues getting rid of the app, check out how to fix Windows when it won't allow you to uninstall a program.

6. Uninstall Any Recent Windows Updates

Sometimes, Windows display the “Application failed because no QT platform plugin could be initialized” error after a system update. In this case, you can load a restore point to undo the change and get rid of the error.

But if there’s no restore point available, you can manually uninstall Windows updates.

1. Launch Windows Settings by pressing Win + I.
2. From the left pane, click Windows Update > Update History.
3. Head to Related Settings and click Uninstall updates.
4. Right-click the latest update and select Uninstall.

Get Rid of the QT Error on Windows

Hopefully, one or more of the above solutions helped you fix the “Application failed to start because no Qt platform plugin could be initialized” error.

Sometimes, it’s difficult to figure out the exact cause of a Windows error, and reinstalling the app every time might not be the most efficient solution. To speed up the troubleshooting process, you should use one of the many Windows repair tools.

This article explains how to download and install the Dropbox desktop app on a Windows, Mac, or Linux computer. If you’re running Windows 10 in S mode, learn how to install Dropbox Lite.

If you‘d like to access Dropbox on your mobile device, learn how to download the Dropbox mobile app.

After you install the Dropbox desktop app on your computer, you can access Dropbox from the icon in your taskbar (Windows) or menu bar (Mac) or the Dropbox folder in File Explorer (Windows) or Finder (Mac).

Any changes you make to your files in the Dropbox desktop app are automatically synced everywhere you access your files in Dropbox, including your account on dropbox.com.

Learn more about how Dropbox syncs your files.

Download and install the Dropbox desktop app on a Windows, Mac, or Linux computer.

Once installed, you’ll receive a prompt to either log in or create a new account. After logging in, follow the prompts to sync files between your computer and your Dropbox account.

You can access Dropbox from the icon in your taskbar (Windows) or menu bar (Mac) or the Dropbox folder in File Explorer (Windows) or Finder (Mac).

How to install the desktop app with admin privileges

The Dropbox desktop app requires admin privileges to run with full functionality on your computer. This enables multiple different core features of Dropbox, including:

• Sync icons that show the sync status of files and folders
• Right-click context menus for taking quick actions in Dropbox

For most users, the desktop app is automatically installed with admin privileges. However, if you didn't install with admin privileges you can follow the instructions below to do so.

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Note: If you don't have admin rights on your computer (for example if you're using a work computer), you may need to ask your IT department for help.

Install the Dropbox desktop app with admin privileges

1. If you already have Dropbox installed, uninstall the application.
2. Download the Dropbox desktop app.
3. Open the installer.
   • Do not right-click or command-click Run as an Administrator
4. Follow the instructions in the install wizard.
   • If you’re asked for an administrative username and password, enter them or contact your administrator to log in.
   • If you’re not asked for an administrative username and password, you’re already an admin on your computer.
5. Complete the installation and log in to Dropbox.

FAQs about downloading the Dropbox desktop app

Why does the Dropbox desktop app for Mac require Keychain access?

Keychain is a password management system for Mac. Dropbox requires access to your Keychain to help verify your account and to provide another layer of security over the Dropbox desktop app preferences.

• To grant Keychain access to Dropbox, click Allow or Always Allow when prompted. Always Allow is recommended for seamless access.
• Clicking Deny will result in a "Couldn't start Dropbox" error message. For security reasons, Dropbox will not start without access to your Keychain.

What is the Dropbox Web Helper for macOS?

Dropbox Web Helper supports the Dropbox user interface on Mac computers. It only runs when the desktop app is running.

Dropbox Web Helper is an independent process, so it may start and stop at different times than the desktop app. If you adjust your firewall or antivirus software for Dropbox, we recommend similar adjustments for Dropbox Web Helper.

What is the Dropbox system extension?

The Dropbox system extension is automatically installed when you install the Dropbox desktop app. It allows you to open online-only files from File Explorer (Windows), Finder (Mac), or third-party applications.

Notes:

• The Dropbox system extension doesn’t apply macOS 11 or later.
• If you’re on a Dropbox team account, an admin on your team can restrict your ability to install or uninstall the system extension.
• Installation of the Dropbox system extension is not applicable to macOS 11 or later.
  • If you're having issues opening online-only files on macOS 12.3 and above, you can open them directly in Finder.
• If you’re on macOS 10.15 or earlier and experiencing issues installing the Dropbox system extension, you may need to update your system preferences to allow the blocked system extension. Learn how to update your system preferences.

If you’re on Windows, macOS 11 or earlier, or Linux, and you’re having issues opening online-only files in the Dropbox desktop app, you may be missing the Dropbox system extension.