Always check mod compatibility with your game version and verify SHA or checksums for downloads.
Extract dinput8.dll and dinput8.ini into your game's Bin32 folder. Original 2007 PC Port (Ubisoft/Sourcenext) Download Resident Evil 4 Pc Mouse Support
If you cannot get the mod working, an even simpler solution is to use to map your mouse to the right analog stick. It is not perfect (you lose 1:1 precision), but it works without downloading third-party files. Go to Steam > Settings > Controller > Desktop Configuration and bind mouse movement to the right joystick output. Always check mod compatibility with your game version
Q: Why does Resident Evil 4 not have mouse support? A: The game was initially optimized for gamepads, but Capcom later released an official patch that enables mouse support. It is not perfect (you lose 1:1 precision),
"My mouse buttons (MB4/MB5) don't work for knife or map."
Do not search generic "mouse drivers." Go to the authoritative source:
: It introduced a "Modern" aiming scheme that allows for more fluid movement compared to the rigid "Classic" tank controls. Definitive Community Solutions