diff --git a/Classes/foxPlayerInput.uc b/Classes/foxPlayerInput.uc
index 0738792..da35332 100644
--- a/Classes/foxPlayerInput.uc
+++ b/Classes/foxPlayerInput.uc
@@ -4,6 +4,7 @@ class foxPlayerInput extends PlayerInput within PlayerController
 	transient;
 
 var bool bDoInit;
+var bool bDoErrorInit;
 
 var float CachedResScaleX;
 var float CachedDefaultFOV;
@@ -21,6 +22,7 @@ struct WeaponInfo
 };
 var WeaponInfo CachedWeaponInfo;
 
+var globalconfig bool bInputClassErrorCheck;
 var globalconfig float Desired43FOV;
 var globalconfig bool bCorrectZoomFOV;
 var globalconfig bool bCorrectMouseSensitivity;
@@ -46,6 +48,23 @@ exec function SetFOV(float F)
 	CachedResScaleX = default.CachedResScaleX;
 }
 
+//fox: Check various PlayerController classes for correct InputClass (and possibly just add it if missing)
+function CheckControllerInputClass(class<PlayerController> ControllerClass, string FriendlyName)
+{
+	if (ControllerClass.default.InputClass != class'foxPlayerInput') {
+		ClientMessage("foxWSFix: " $ FriendlyName $ " InputClass is: " $ ControllerClass.default.InputClass);
+
+		//Just add InputClass if missing
+		if (ControllerClass.default.InputClass == None) {
+			ClientMessage("foxWSFix: Attempting to add missing InputClass line...");
+			ControllerClass.default.InputClass = class'foxPlayerInput';
+			ControllerClass.static.StaticSaveConfig();
+			ClientMessage("foxWSFix: " $ FriendlyName $ " InputClass is now: " $ ControllerClass.default.InputClass);
+		}
+		ClientMessage("foxWSFix: Please verify User.ini settings!");
+	}
+}
+
 //fox: Hijack this to force FOV per current aspect ratio - done every frame as a lazy catch-all since we're only hooking clientside PlayerInput
 event PlayerInput(float DeltaTime)
 {
@@ -55,6 +74,24 @@ event PlayerInput(float DeltaTime)
 	if (bDoInit) {
 		bDoInit = false;
 
+		//Check for errors if requested
+		if (bInputClassErrorCheck
+		&& (class'PlayerController'.default.InputClass != class'foxPlayerInput' || class'xPlayer'.default.InputClass != class'foxPlayerInput')) {
+			if (bDoErrorInit && Level.TimeSeconds > 3f) {
+				bDoErrorInit = false;
+				ClientMessage("foxWSFix Warning: One or more errors occurred. To skip this error check, set bInputClassErrorCheck=false in User.ini");
+				CheckControllerInputClass(class'PlayerController', "[Engine.PlayerController]");
+				CheckControllerInputClass(class'xPlayer', "[XGame.xPlayer]");
+
+				//Write settings to ini once if stuck on errors
+				SaveConfig();
+			}
+
+			//Just bail here, resetting bDoInit so we don't do our normal hooks
+			bDoInit = true;
+			return;
+		}
+
 		//Write settings to ini if first run
 		SaveConfig();
 
@@ -260,6 +297,8 @@ function InvertMouse(optional string Invert)
 defaultproperties
 {
 	bDoInit=true
+	bDoErrorInit=true
+	bInputClassErrorCheck=true
 	Desired43FOV=90f
 	bCorrectZoomFOV=true
 	bCorrectMouseSensitivity=true
diff --git a/readme.md b/readme.md
index 1ae445c..a4402ec 100644
--- a/readme.md
+++ b/readme.md
@@ -1,4 +1,4 @@
-foxWSFix v2.1.0
+foxWSFix v2.1.1
 ===============
 Improved widescreen support for Unreal Tournament 2004
 
@@ -7,7 +7,7 @@ Features
 * Aspect-correct "Hor+" FOV adjustment, including vehicle and weapon zoom values
 * Aspect-correct rendering for first-person weapons
 * Aspect-correct HUD support (mostly), based on Azarael's HUD Scaling Fix mutator
-* Aspect-correct mouse sensitivity (auto-adjusts on resolution change)
+* Aspect-correct mouse sensitivity (scale off wider FOV instead of hard-coded 90)
 * Entirely client-side - no mutators required
 
 Install / Uninstall
@@ -23,7 +23,8 @@ Replace every instance of it with the following:
     ;InputClass=Class'Engine.PlayerInput'
     InputClass=Class'foxWSFix.foxPlayerInput'
 
-(Note: This line may appear multiple times - be sure to change each one if so!)
+**Note:** This line should appear *at least twice* - once under `[Engine.PlayerController]`, and
+once under `[XGame.xPlayer]`. Be sure to change each one! (or add it if missing)
 
 You're done! To uninstall, simply reverse your changes.
 
@@ -60,9 +61,10 @@ However, widescreen HUDs are provided for vanilla HUDs only.
 foxWSFix stores its settings in System\User.ini as such:
 
     [foxWSFix.foxPlayerInput]
+    bInputClassErrorCheck=True      ;Check User.ini InputClass settings for possible errors?
     Desired43FOV=90.000000          ;Desired 4:3 FOV per SetFOV command / menu setting
     bCorrectZoomFOV=True            ;Correct FOV values for weapon zoom?
-    bCorrectMouseSensitivity=True   ;Correct MouseSensitivity for aspect ratio changes?
+    bCorrectMouseSensitivity=True   ;Correct MouseSensitivity for aspect ratio changes? (due to wider FOV)
     Desired43MouseSensitivity=2.200000 ;Desired 4:3 MouseSensitivity per SetSensitivity command / menu setting
     WideHUDMap=(HudClass=Class'UT2k4Assault.HUD_Assault',WideHUD="foxWSFix.foxWideHUD_Assault")
     WideHUDMap=(HudClass=Class'XInterface.HudCBombingRun',WideHUD="foxWSFix.foxWideHudCBombingRun")
@@ -118,6 +120,11 @@ And of course, thanks for trying the mod!
 
 Changes
 -------
+v2.1.1 (2020-06-24):
+* Added in-game InputClass error handling to hopefully ease some install issues
+* Updated installation instructions to reflect the above
+* Clarified bCorrectMouseSensitivity (Unreal normally scales sensitivity against a hard-coded 90 FOV for zoom)
+
 v2.1.0 (2020-02-27):
 * Resolved AntiTCC issue with GUIController hook (see "v2.0 Upgrade Note" above)
   * (Note: All functionality is still in place, just handled in foxPlayerInput now)