diff --git a/dev/AppLifecycle/Association.cpp b/dev/AppLifecycle/Association.cpp
index f08a7e5ed4..9cbb6d443c 100644
--- a/dev/AppLifecycle/Association.cpp
+++ b/dev/AppLifecycle/Association.cpp
@@ -26,6 +26,17 @@ namespace winrt::Microsoft::Windows::AppLifecycle::implementation
             seed = wil::GetModuleFileNameW<std::wstring>(nullptr);
         }
 
+        // Convert to lowercase if it appears to be a file path to ensure case insensitivity
+        if (!seed.empty() && 
+            (seed.find(L'\\') != std::wstring::npos || 
+             (seed.size() > 1 && seed[1] == L':')))
+        {
+            // Make a mutable copy of the string
+            std::wstring lowercaseSeed = seed;
+            CharLowerW(&lowercaseSeed[0]);
+            seed = lowercaseSeed;
+        }
+
         std::hash<std::wstring> hasher;
         auto hash = hasher(seed);
         uint64_t hash64 = static_cast<uint64_t>(hash);
diff --git a/test/AppLifecycle/FunctionalTests.cpp b/test/AppLifecycle/FunctionalTests.cpp
index 3f969ee795..9159cfb398 100644
--- a/test/AppLifecycle/FunctionalTests.cpp
+++ b/test/AppLifecycle/FunctionalTests.cpp
@@ -406,5 +406,25 @@ namespace Test::AppLifecycle
             Execute(L"AppLifecycleTestApp.exe", L"/UnregisterProtocol", g_deploymentDir);
             WaitForEvent(event, m_failed);
         }
+
+        TEST_METHOD(FileTypeActivation_CaseInsensitivity)
+        {
+            // This test verifies that ComputeAppId is case-insensitive for file paths
+            // by checking that two paths that differ only by case produce the same AppId
+
+            // Get implementation namespace to access ComputeAppId
+            using namespace winrt::Microsoft::Windows::AppLifecycle::implementation;
+
+            // Test paths with different case
+            std::wstring path1 = L"C:\\Users\\user\\App\\app.exe";
+            std::wstring path2 = L"C:\\Users\\user\\App\\App.exe";
+            
+            // Verify that the AppIds calculated from the paths are the same
+            auto appId1 = ComputeAppId(path1);
+            auto appId2 = ComputeAppId(path2);
+            
+            // The AppIds should be identical regardless of the case
+            VERIFY_ARE_EQUAL(appId1, appId2);
+        }
     };
 }
diff --git a/test/AppLifecycle/pch.h b/test/AppLifecycle/pch.h
index 26d190ff0c..fd553d7550 100644
--- a/test/AppLifecycle/pch.h
+++ b/test/AppLifecycle/pch.h
@@ -31,5 +31,8 @@
 #include <winrt/Windows.System.h>
 #include <winrt/Microsoft.Windows.AppLifecycle.h>
 
+// Include Association.h for implementation namespace access
+#include "../../dev/AppLifecycle/Association.h"
+
 #include <WindowsAppRuntime.Test.Bootstrap.h>
 namespace TP = ::Test::Packages;