diff --git a/demo/DemoApp/Demos/Basic.cs b/demo/DemoApp/Demos/Basic.cs
index d24f88de..593a7480 100644
--- a/demo/DemoApp/Demos/Basic.cs
+++ b/demo/DemoApp/Demos/Basic.cs
@@ -56,7 +56,7 @@ public async Task Run(CancellationToken ct = default)
                 outcome = true;
             });
 
-            resultList.OnFail(() => {
+            resultList.OnFail((eventName) => {
                 outcome = false;
             });
 
diff --git a/demo/DemoApp/Demos/BasicWithCustomTypes.cs b/demo/DemoApp/Demos/BasicWithCustomTypes.cs
new file mode 100644
index 00000000..a8bc4354
--- /dev/null
+++ b/demo/DemoApp/Demos/BasicWithCustomTypes.cs
@@ -0,0 +1,73 @@
+// Copyright (c) Microsoft Corporation.
+//  Licensed under the MIT License.
+
+using RulesEngine.Models;
+using System;
+using System.Collections.Generic;
+using System.Dynamic;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using static RulesEngine.Extensions.ListofRuleResultTreeExtension;
+
+namespace DemoApp.Demos
+{
+    public class BasicWithCustomTypes
+    {
+        internal static class Utils
+        {
+            public static bool CheckContains(string check, string valList)
+            {
+                if (String.IsNullOrEmpty(check) || String.IsNullOrEmpty(valList))
+                    return false;
+
+                var list = valList.Split(',').ToList();
+                return list.Contains(check);
+            }
+        }
+        public async Task Run(CancellationToken ct = default)
+        {
+            Console.WriteLine($"Running {nameof(BasicWithCustomTypes)}....");
+            var workflows = new List<Workflow>();
+            var workflow = new Workflow();
+            workflow.WorkflowName = "Test Workflow Rule 1";
+
+            var rules = new List<Rule> {
+                new Rule() {
+                    RuleName = "Test Rule",
+                    SuccessMessage = "doSomething ran successfully",
+                    ErrorMessage = "doSomething failed",
+                    Expression = "Utils.CheckContains(string1, \"bye,seeya,hello\") == true",
+                    RuleExpressionType = RuleExpressionType.LambdaExpression
+                }
+            };
+            
+            workflow.Rules = rules;
+            workflows.Add(workflow);
+
+            var reSettings = new ReSettings {
+                CustomTypes = [ typeof(Utils) ]
+            };
+
+            var bre = new RulesEngine.RulesEngine(workflows.ToArray(), reSettings);
+
+            var string1 = new RuleParameter("string1", "hello");
+            
+            var ruleResultTree = await bre.ExecuteAllRulesAsync("Test Workflow Rule 1", [string1], ct);
+            ruleResultTree.OnSuccess((eventName) => {
+                Console.WriteLine($"Result '{eventName}' is as expected.");
+            });
+            ruleResultTree.OnFail((eventName) => {
+                Console.WriteLine($"Test outcome: false");
+            });
+
+            var actionRuleResult = await bre.ExecuteActionWorkflowAsync("Test Workflow Rule 1", "Test Rule", [string1], ct);
+            actionRuleResult.Results.OnSuccess((eventName) => {
+                Console.WriteLine($"Result '{eventName}' is as expected.");
+            });
+            actionRuleResult.Results.OnFail((eventName) => {
+                Console.WriteLine($"Test outcome: false");
+            });
+        }
+    }
+}
diff --git a/demo/DemoApp/Demos/EF.cs b/demo/DemoApp/Demos/EF.cs
index 28a9fbd4..7261ad0c 100644
--- a/demo/DemoApp/Demos/EF.cs
+++ b/demo/DemoApp/Demos/EF.cs
@@ -70,7 +70,7 @@ public async Task Run(CancellationToken ct = default)
                     discountOffered = $"Discount offered is {eventName} % over MRP.";
                 });
 
-                resultList.OnFail(() => {
+                resultList.OnFail((eventName) => {
                     discountOffered = "The user is not eligible for any discount.";
                 });
 
diff --git a/demo/DemoApp/Demos/JSON.cs b/demo/DemoApp/Demos/JSON.cs
index a6cd5820..583e07c0 100644
--- a/demo/DemoApp/Demos/JSON.cs
+++ b/demo/DemoApp/Demos/JSON.cs
@@ -53,7 +53,7 @@ public async Task Run(CancellationToken ct = default)
                 discountOffered = $"Discount offered is {eventName} % over MRP.";
             });
 
-            resultList.OnFail(() => {
+            resultList.OnFail((eventName) => {
                 discountOffered = "The user is not eligible for any discount.";
             });
 
diff --git a/demo/DemoApp/Demos/NestedInput.cs b/demo/DemoApp/Demos/NestedInput.cs
index 2e99bc3d..fe649d5e 100644
--- a/demo/DemoApp/Demos/NestedInput.cs
+++ b/demo/DemoApp/Demos/NestedInput.cs
@@ -59,7 +59,7 @@ public async Task Run(CancellationToken ct = default)
 
                 resultList.OnSuccess((eventName) => {
                     Console.WriteLine($"{workflow.WorkflowName} evaluation resulted in success - {eventName}");
-                }).OnFail(() => {
+                }).OnFail((eventName) => {
                     Console.WriteLine($"{workflow.WorkflowName} evaluation resulted in failure");
                 });
             }
diff --git a/demo/DemoApp/Program.cs b/demo/DemoApp/Program.cs
index d744373a..959222cd 100644
--- a/demo/DemoApp/Program.cs
+++ b/demo/DemoApp/Program.cs
@@ -19,6 +19,7 @@ public static async Task Main(string[] args)
                 //cts.CancelAfter(TimeSpan.FromMilliseconds(94));
 
                 await new Demos.Basic().Run(cts.Token);
+                await new Demos.BasicWithCustomTypes().Run(cts.Token);
                 await new Demos.JSON().Run(cts.Token);
                 await new Demos.NestedInput().Run(cts.Token);
                 await new Demos.EF().Run(cts.Token);
diff --git a/src/RulesEngine/Extensions/ListofRuleResultTreeExtension.cs b/src/RulesEngine/Extensions/ListofRuleResultTreeExtension.cs
index fc571ce8..b01db3b8 100644
--- a/src/RulesEngine/Extensions/ListofRuleResultTreeExtension.cs
+++ b/src/RulesEngine/Extensions/ListofRuleResultTreeExtension.cs
@@ -11,7 +11,7 @@ namespace RulesEngine.Extensions
     public static class ListofRuleResultTreeExtension
     {
         public delegate void OnSuccessFunc(string eventName);
-        public delegate void OnFailureFunc();
+        public delegate void OnFailureFunc(string eventName);
 
 
         /// <summary>
@@ -40,9 +40,13 @@ public static List<RuleResultTree> OnSuccess(this List<RuleResultTree> ruleResul
         /// <returns></returns>
         public static List<RuleResultTree> OnFail(this List<RuleResultTree> ruleResultTrees, OnFailureFunc onFailureFunc)
         {
-            bool allFailure = ruleResultTrees.All(ruleResult => ruleResult.IsSuccess == false);
-            if (allFailure)
-                onFailureFunc();
+            var allFailure = ruleResultTrees.FirstOrDefault(ruleResult => ruleResult.IsSuccess == false);
+            if (allFailure != null)
+            {
+                var eventName = allFailure.Rule.ErrorMessage ?? allFailure.Rule.RuleName;
+                onFailureFunc(eventName);
+            }
+
             return ruleResultTrees;
         }
     }
diff --git a/test/RulesEngine.UnitTest/ListofRuleResultTreeExtensionTest.cs b/test/RulesEngine.UnitTest/ListofRuleResultTreeExtensionTest.cs
index f0184cf9..b2d97d62 100644
--- a/test/RulesEngine.UnitTest/ListofRuleResultTreeExtensionTest.cs
+++ b/test/RulesEngine.UnitTest/ListofRuleResultTreeExtensionTest.cs
@@ -164,7 +164,7 @@ public void OnFailWithSuccessTest()
 
             var successEventName = true;
 
-            rulesResultTree.OnFail(() => {
+            rulesResultTree.OnFail((eventName) => {
                 successEventName = false;
             });
 
@@ -203,7 +203,7 @@ public void OnFailWithoutSuccessTest()
 
             var successEventName = true;
 
-            rulesResultTree.OnFail(() => {
+            rulesResultTree.OnFail((eventName) => {
                 successEventName = false;
             });