Software & Apps Windows How to Fix D3dcompiler_42.dll Not Found or Missing Errors A Troubleshooting Guide for D3dcompiler_42.dll Errors by Tim Fisher General Manager, VP, Lifewire.com Tim Fisher has 30+ years' professional technology support experience. He writes troubleshooting content and is the General Manager of Lifewire. our editorial process Facebook Twitter LinkedIn Tim Fisher Updated on February 21, 2020 Windows The Ultimate Laptop Buying Guide Tweet Share Email D3dcompiler_42.dll issues are caused in one way or another by an issue with Microsoft DirectX. The d3dcompiler_42.dll file is one of many files contained in the DirectX software collection. Since DirectX is utilized by most Windows based games and advanced graphics programs, d3dcompiler_42.dll errors usually show up only when using these programs. Any of Microsoft's operating systems since Windows 98 may be affected by d3dcompiler_42.dll and other DirectX issues. This includes Windows 10, Windows 8, Windows 7, Windows Vista, Windows XP, and Windows 2000. D3dcompiler_42.dll Errors There are several ways that d3dcompiler_42.dll errors can show up on your computer. Here are several of the more common ways you might see d3dcompiler_42.dll errors: D3dcompiler_42.dll not found. Reinstalling might help fix this.The file d3dcompiler_42.dll is missingD3dcompiler_42.DLL Not FoundFile d3dcompiler_42.dll not found The d3dcompiler_42.dll error message could apply to any program that utilizes Microsoft DirectX, most commonly video games. The d3dcompiler_42 DLL errors appear when the game or other software program is started. How to Fix D3dcompiler_42.dll Errors Do not download the d3dcompiler_42.dll DLL file individually from any "DLL download site." There are a number of excellent reasons that downloading DLLs from these sites are never a good idea. If you've already downloaded d3dcompiler_42.dll, remove it from wherever you put it and continue with these steps. Restart your computer if you haven't yet. The d3dcompiler_42.dll error might be a fluke and a simple restart could clear it up completely. Install the latest version of Microsoft DirectX. Chances are, upgrading to the latest version of DirectX will fix the d3dcompiler_42.dll not found error. The same DirectX installation program works with all versions of Windows including Windows 7, 8, 10, Vista, XP, and more. It will replace any missing DirectX 11, DirectX 10, or DirectX 9 file. Microsoft often releases updates to DirectX without updating the version number or letter, so be sure to install the latest release even if your version is technically the same. Assuming the latest DirectX version from Microsoft doesn't fix the d3dcompiler_42.dll error, look for a DirectX installation program on your game or application DVD or CD. Sometimes the software developers will include a copy of DirectX on the installation disc if their game or program utilizes DirectX. Sometimes, though not often, the DirectX version included on the disc is a better fit for the program than the latest version available from Microsoft. Uninstall the game or software program and then reinstall it again. Something might have happened to the files in the program that work with d3dcompiler_42.dll and a reinstall could do the trick. Restore the d3dcompiler_42.dll file from the latest DirectX software package. If the above troubleshooting steps haven't worked to solve your d3dcompiler_42.dll error, try extracting the d3dcompiler_42.dll individually from the DirectX downloadable package. Update the drivers for your video card. While it's not the most common solution, in some situations updating the drivers for the video card in your computer could correct this DirectX issue. Need More Help? If you're not interested in fixing this problem yourself, see How Do I Get My Computer Fixed? for a full list of your support options, plus help with everything along the way like figuring out repair costs, getting your files off, choosing a repair service, and a whole lot more.