As is the case with any software out there, League of Legends is susceptible to a variety of errors presented at launching the game or otherwise. One of the most common issues is the ‘d3dx9_39.dll is missing’ popup that plagues players, especially on newer machines.
But, this is an easy and simple fix and we’ve got you covered.
Download DirectX 9
All games released on Windows require a DirectX library to run. DirectX is an official Microsoft api that provides the framework for nearly every software created for the Windows operating system. Having been released in 2009., League of Legends is fairly dated in terms of software and requires an older DirectX library to function properly.
New operating systems like Windows 10 and 11 come with DirectX 11 and 12 pre-installed, but don’t contain all the files of older versions, including the problematic ‘d3dx9_39.dll’. Thankfully, this is easily fixable. You can download the official DirectX setup and run it on your PC.
After installing the software, restart your computer and give the game a try. It should now function properly as it has all the background files necessary to run. Keep in mind that your PC might not support DirectX 9, though this is rarely the case.
All graphics cards released in the last 15 years support DirectX 9. However, in case you found your PC at an archeological excavation site, you can check out CanYouRunIt and see if you can play the game at all.
Software tends to act funny and present problems that frequently leave us scratching our heads. However, the fix is usually simple and quick, just like with this incessant issue. We hope this guide has helped you get League of Legends running and blast away on the Summoner’s Rift!