diff --git a/src/Stateless/TransitionGuard.cs b/src/Stateless/TransitionGuard.cs
index 2b9dbf2b..ae1dcb58 100644
--- a/src/Stateless/TransitionGuard.cs
+++ b/src/Stateless/TransitionGuard.cs
@@ -16,22 +16,52 @@ internal class TransitionGuard
 
             public static Func<object[], bool> ToPackedGuard<TArg0>(Func<TArg0, bool> guard)
             {
-                return args => guard(ParameterConversion.Unpack<TArg0>(args, 0));
+                return args =>
+                {
+                    try
+                    {
+                        return guard(ParameterConversion.Unpack<TArg0>(args, 0));
+                    }
+                    catch (ArgumentException)
+                    {
+                        return false;
+                    }
+                };
             }
 
             public static Func<object[], bool> ToPackedGuard<TArg0, TArg1>(Func<TArg0, TArg1, bool> guard)
             {
-                return args => guard(
-                    ParameterConversion.Unpack<TArg0>(args, 0), 
-                    ParameterConversion.Unpack<TArg1>(args, 1));
+                return args =>
+                {
+                    try
+                    {
+                        return guard(
+                            ParameterConversion.Unpack<TArg0>(args, 0),
+                            ParameterConversion.Unpack<TArg1>(args, 1));
+                    }
+                    catch (ArgumentException)
+                    {
+                        return false;
+                    }
+                };
             }
 
             public static Func<object[], bool> ToPackedGuard<TArg0, TArg1, TArg2>(Func<TArg0, TArg1, TArg2, bool> guard)
             {
-                return args => guard(
-                    ParameterConversion.Unpack<TArg0>(args, 0),
-                    ParameterConversion.Unpack<TArg1>(args, 1),
-                    ParameterConversion.Unpack<TArg2>(args, 2));
+                return args =>
+                {
+                    try
+                    {
+                        return guard(
+                            ParameterConversion.Unpack<TArg0>(args, 0),
+                            ParameterConversion.Unpack<TArg1>(args, 1),
+                            ParameterConversion.Unpack<TArg2>(args, 2));
+                    }
+                    catch (ArgumentException)
+                    {
+                        return false;
+                    }
+                };
             }
 
             public static Tuple<Func<object[], bool>, string>[] ToPackedGuards<TArg0>(Tuple<Func<TArg0, bool>, string>[] guards)
diff --git a/test/Stateless.Tests/TriggerWithParametersFixture.cs b/test/Stateless.Tests/TriggerWithParametersFixture.cs
index 3c2890f2..129ef2ea 100644
--- a/test/Stateless.Tests/TriggerWithParametersFixture.cs
+++ b/test/Stateless.Tests/TriggerWithParametersFixture.cs
@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using Xunit;
 
 namespace Stateless.Tests
@@ -73,5 +75,30 @@ public void ParameterListOfCorrectTypeAreAccepted()
             var twp = new StateMachine<State, Trigger>.TriggerWithParameters(Trigger.X, new Type[] { typeof(int), typeof(string) });
             twp.ValidateParameters(new object[] { 123, "arg" });
         }
+
+        /// <summary>
+        /// Issue #450 - GetPermittedTriggers throws exception when triggers have different parameter types.
+        /// </summary>
+        [Theory]
+        [MemberData(nameof(DifferentTypeTriggersData))]
+        public void DifferentTypeTriggersThrowNoException(params object[] arg)
+        {
+            var fsm = new StateMachine<State, Trigger>(State.A);
+            StateMachine<State, Trigger>.TriggerWithParameters<bool> twp1 = fsm.SetTriggerParameters<bool>(Trigger.X);
+            StateMachine<State, Trigger>.TriggerWithParameters<int, string> twp2 = fsm.SetTriggerParameters<int, string>(Trigger.Y);
+            StateMachine<State, Trigger>.TriggerWithParameters<string, int, bool> twp3 = fsm.SetTriggerParameters<string, int, bool>(Trigger.Z);
+            fsm.Configure(State.A)
+                .PermitIf(twp1, State.B, p1 => true)
+                .PermitIf(twp2, State.C, (p1, p2) => true)
+                .PermitIf(twp3, State.D, (p1, p2, p3) => true);
+            Assert.Equal(1, fsm.GetPermittedTriggers(arg).Count());
+        }
+
+        public static IEnumerable<object[]> DifferentTypeTriggersData()
+        {
+            yield return new object[] { "arg", 123, true };
+            yield return new object[] { 123, "arg" };
+            yield return new object[] { true };
+        }
     }
 }