Because the original PC version of Call of Duty: Modern Warfare 3 (2011) lacks native controller support, players use Xpadder to map keyboard and mouse inputs to their gamepads.

: Ensure your in-game keybinds in MW3 match the keys assigned in Xpadder. For example, if Xpadder's "Fire" is set to "Left Mouse Button," the in-game "Fire" must also be set to "Left Mouse Button". Optimization Tips Xpadder call of duty modern warfare 3 profile

(2011) on PC—specifically the SKIDROW release or other versions that lack native controller support—you've likely realized your gamepad won't work out of the box. To bridge the gap, gamers often turn to Xpadder, a powerful utility that maps keyboard and mouse commands directly to your controller's buttons.

Part 7: Recommended Game Settings for Controller Users

Because Xpadder emulates a mouse, you must optimize MW3’s settings for analog-style play: