How to Fix “d3dx9_42.dll is missing” Error on Windows?

Recently, several users reported that their screens display an error code stating either “D3dx9_42.dll Not Found” or “The file d3dx9_42.dll is missing“ when they attempt to launch a game or a graphic program. 

It appears that the missing or not found d3dx9_42.dll error is typically caused by issues within the Windows DirectX. In case you do not know already, Microsoft DirectX is a set of low-level APIs that provide hardware-accelerated multimedia support to Windows programs. DirectX allows the program to analyze the hardware capabilities of your computer and then adjusts the parameters accordingly.

Here is why you might be facing the issue at hand:

  • DirectX Files are corrupt: In most cases, you might be experiencing problems launching games because the DirectX is that either the files are corrupt or out-of-date. This problem is usually resolved by refreshing the DX files.
  • Third-party software conflict: There are times when third-party software installed on your computer interferes with the legitimate processes of your programs and games, leading to errors like the one at hand. This is typically caused by third-party antivirus programs.
  • D3dx9_42.dll is missing: If the d3dx9_42.dll is not installed on your computer or has gotten deleted accidentally, you will end up facing the issue at hand.

Now that we know what might be causing the issue, let’s have a look at the effective troubleshooting steps that will help you fix it in no time. 

Install the d3dx9_42.dll File

As mentioned earlier, the error codes typically state that the d3dx9_42.dll is missing, which means in most cases, you can resolve the problem by installing the file again. Here is how you can do that:

  1. Launch your browser and download the Client.
  2. Install the application and run it.
  3. Once the application is launched, type d3dx9_42.dll in the search bar and click on the Search for DLL file button.

    Click the Search for th DLL file
  4. Click d3dx9_42.dll in the search result and then click Install.
  5. Once the file is installed successfully, check if you can now run the desired game without the d3dx9_42.dll issue.

Install DirectX End-User Runtimes

DirectX End-User Runtimes package contains DirectX 9.0c and older versions updates that can also help you fix the issue at hand. If the first method did not work for you, here is how you can install DirectX end-user runtimes to fix the issue:

  1. Navigate to the Windows End-User Runtimes download page.
  2. Choose a language and then click on the Download button.

    Download DirectX End-User Runtimes
  3. Once the file is downloaded, click on it and follow the on-screen instructions to install it. 
  4. Once done, restart your computer and see if the d3dx9_42.dll issue is resolved.

Install Updates

It is also common for such errors to show up if you are using an outdated version of DirectX. Microsoft includes DirectX updates with the latest Windows updates, which means you can update the utility to its latest version by installing any pending Windows updates. 

Here is how you can do that:

  1. Press Windows + I keys simultaneously on your keyboard to open Windows Settings.
  2. In the Settings window, select Updates & Security.

    Open Update & Security
  3. Now click on the Check for updates and wait for the scan to complete. If any updates are found, install them and check if the issue is resolved.

    Check for Windows Updates

Disable Antivirus

There are times when third-party antivirus programs interfere with the legitimate processes of the applications installed on your computer, resulting in issues like the one at hand. These are mostly just false alarms, and if this scenario is applicable, disabling the antivirus software can do the trick for you. 

We recommend that you disable the antivirus temporarily at first and then check if doing so resolves the d3dx9_42.dll issue. If it does, it is best to switch to another antivirus program that offers better services.

Update GPU Drivers

As it turns out, outdated drivers can cause programs and games, and sometimes even the whole operating system, to crash. To prevent issues like the one at hand and enjoy the best possible gaming experience, you must keep your drivers up-to-date. 

If you haven’t installed the latest GPU updates on your PC, here is how you can do it:

  1. Type Device Manager in the search area of the taskbar and hit Open.
  2. Once you are inside the Device Manager window, locate and expand the Display adapters section.
  3. Right-click on your graphics drivers and select Update driver.

    Updating the GPU driver
  4. Now select Search automatically for drivers and wait for the system to scan for updates. If any updated drivers are found, install them.

    Search automatically for new drivers
  5. Alternatively, if you want to want to install the updates manually, follow steps 1-3 again but this time, select Properties from the context menu.

    Launch display adapter properties
  6. In the Properties dialog, select the Details tab.
  7. Now, head over to the Property field and select Hardware IDs from the drop-down menu.

    Manually update display driver
  8. Copy the first value from the list displayed on your screen by right-clicking on it.
  9. Paste the copied value into the search engine in your browser and search for its latest version.
  10. When you have installed the driver, restart your computer, and you shouldn’t see the d3dx9_42.dll error anymore when launching games or programs.

Run SFC Command

In some cases, you might also be facing the issue at hand if your operating system is infected with a virus or a generic corruption error. 

In Windows, you can find several built-in troubleshooting utilities that can help you identify problems and then resolve them with little or no user interaction. System File Checker is one of these utilities, which allows you to repair corrupt system files in Windows. With SFC, during the scanning process, all protected system files are examined, and damaged ones are replaced with cached copies of them.

Many users were able to resolve the issue by running an SFC command, so you should give it a try as well. If that doesn’t work, read on for the next method.

Reinstall the Problematic Application

There is a possibility that the program or game you are trying to run has a corrupted system file, which is preventing you from loading it. If running an SFC command did not help you, you can try reinstalling the application. 

The installation files are likely to have the correct version of the d3dx9_42.dll file, which will fix your problem.  Here is what you need to do:

  1. Press Windows + R keys simultaneously on your keyboard to open a Run dialog box.
  2. In the text field of the dialog box, type appwiz.cpl and hit Enter.

    Open up the Programs and Features menu
  3. Once you are inside the Programs & Features window, right-click on the program that is causing the issue and select Uninstall.

    Uninstall the Antivirus
  4. After the uninstallation process is complete, restart your PC.
  5. Upon reboot, install the program again and check if the d3dx9_42.dll issue is fixed.

Zainab Falak

Zainab Falak is a highly educated professional with a background in actuarial science and a strong passion for technology. Her expertise lies in the field of data analytics and she is a proficient programmer in languages such as Python and R. At Appuals, Zainab shares her extensive knowledge of Windows 8, 10, and 11, covering a broad range of topics related to these operating systems. Zainab's ability to effectively communicate technical concepts in a clear and concise manner has earned her recognition and respect in the tech community. She is committed to staying up-to-date with the latest developments in the field and providing readers with insightful and informative content.