When it comes to common errors in Windows 10, 7, and 8, one of the most common operating system errors is related to the D3DX9_30.dll file. Some users have described the error as appearing when trying to run a certain application in the form of a pop-up window. “The program can’t start because D3DX9_30.dll is missing,” “D3DX9_30.dll is missing from your computer,” “What to do when D3DX9_30.dll is missing” … Most of these errors have easy solutions, which we’ll explain below using several methods.
Solution to the D3DX9_30.dll error in Windows 10
Often, errors related to the D3DX9_30.dll file are related to the Visual Studio C++ library. To resolve any errors related to this file, we’ll need to reinstall the library. First, we’ll need to know our computer’s architecture, which will tell us which version we’ll need to download .
To do this, right-click the Windows icon in the Start menu and then select the System option . In the System Type section, you can find out your computer’s architecture. Now, all you need to do is download the version compatible with your computer: x86 for 32-bit computers and x64 for 64-bit computers.
- Download Visual Studio C++
Finally, we’ll install the program following the usual process. Finally, we’ll restart the computer for the changes to take effect .
Download D3DX9_30.dll to install it manually
The above method does not work, the next thing we have to do is download the file manually to install it in the relevant directory.
Once downloaded, we will go to the following path to paste the file into the root of the folder:
- Local disk C:/Windows/System32
If our computer is 32-bit, we will also have to paste the file in the following path:
- Local disk C:/Windows/ SysWOW64
Move the D3DX9_30.dll file to the program execution path
The last option before resorting to the Windows command prompt is to move the file we just downloaded to the execution path of the program that’s generating the error. To do this, right-click the program icon on the Windows desktop and then select the Open file location option , as shown in the following screenshot.
In the root of the folder that will open next, we will paste the D3DX9_30.dll file to force its detection when opening the program.
And if none of the above works…
Then we’ll have to use CMD, which we can access by typing the program name in the Windows search bar.
Before running the program, we’ll right-click on its icon and click Open with administrative privileges . Once inside, we’ll type the following command:
- sfc /scannow
Windows will now run a diagnostic tool that will search for and repair any corrupt or missing files. However, the process may take several minutes , depending on the hard drive’s read and write speed
