By default, modern Steam copies launch the DX10 version. But some fan patches, "No-GFWL" (Games for Windows Live) fixes, and classic cheat tables are hardcoded to look for RE5DX9.exe .
Searching for a resident evil 5 re5dx9 exe download usually happens when the game won't launch or you're getting a "missing executable" error on Steam. This specific file is the DirectX 9 version of the game's launcher. How to Fix or Reinstall the RE5DX9.EXE
If you are trying to bypass the defunct Games for Windows Live system, use the Installing Without GfWL guide to run the game directly. Manual Modding & Configuration
