DxO PhotoLab was unable to start. This is usually because DirectX is not properly installed

This information applies to version(s): 1, 2, 3, 4

1 / Go to the website of the manufacturer of your graphics card, download and install the latest driver for your graphics card

2 / Rename the file "C:\Windows\System32\D3DX9_42.dll" in "C:\Windows\System32\D3DX9_42.dllold" and install DirectX 9.1c and DirectX 11