I'm trying to install Fallout 3 on my dad's computer, which is running Windows 10. However, every time he installs the game and tries to run it, he's given this error message.

"The code execution cannot proceed because d3dx9_38.dll was not found. Reinstalling the program may fix this problem."

I bought both Fallout 3 and Fallout New Vegas for him a week or so ago (back when it was still on sale). I saved the installers to a jump drive and transferred them to his computer. I'm thinking that the issue is that something got corrupted when transferring the files over, so I'm re-downloading them again to see if it was an issue with the installer. However, I wanted to ask and see if there was another reason why the error message keeps popping up.

Is it possible that I need to install an older version of DirectX? I read in another post that there's an option to select which version of DirectX the game uses, but I couldn't find a way to adjust it.

UPDATE: I tried re-downloading the installer, but it made no difference. I tried downloading a DirectX package from Microsoft's website and copying the 'd3dx9_38.dll' into the Windows/System32 folder, but it still did no good; I still get the error message.

I'll give that a try when I'm able to see if it works. Thank you.

However, I've run into a new error code. After I tried copying the 'd3dx9_38.dll' into both the Win32 folder and the Fallout 3 folder, I restarted the computer and tried running the game again and got this message:

"The application was unable to start correctly (0xc000007b). Click OK to close the application."

The searches I did say that this was tied to Games for Windows Live, which I don't understand since the GOG release strips out GFLW. I tried downloading the GFLW Disabler for Fallout 3, but it can't find the Fallout.ini file.

I'll try downloading the DirectX 9.0c installer an give that a try when as soon as I can (I have to leave for work soon), but I was wondering if the new error code was tied to something else.

DirectX End-User Runtimes (June 2010)
https://www.microsoft.com/en-us/download/details.aspx?id=8109

That did the trick. I had to install it instead of just extracting the .dll files. I got confused because you the file you first download only installs or extracts all the .dll archives. The actual DirectX installer is buried in there, and after running that installer, Fallout 3 was able to run.

Thank you again.

Glad to have helped.
Now, for safety purpose, you should download the DirectX web installer and use it as well: it will check your DirectX installation, update it and fix any issue.

Say hello to your dad Roger Wilco.

Go with the patch to fix this issue.

Apply the below-given steps to apply the patch:

First, you have to download the patch from the official site of this game

Extract the downloaded patch on your desktop and open the patch

Choose the folder where you installed the game, in case of default Steam folder the path of game is: “C:\Program Files (x86)\Steam\Steamapps\common\Fallout 4″

Choose your graphics card:AMD or Nvidia and click on the check to confirm

After it choose your errors from the box in the right

At last, simply clickVerify&Patch and wait until the patch finishes.


Source: http://www.pcerror-fix.com/complete-steps-to-fix-fallout-4-crashes-errors-performance-issues-lag-low-fps