diff --git a/dev/AppLifecycle/AppInstance.cpp b/dev/AppLifecycle/AppInstance.cpp
index 5631cb3872..3434ad860e 100644
--- a/dev/AppLifecycle/AppInstance.cpp
+++ b/dev/AppLifecycle/AppInstance.cpp
@@ -291,7 +291,7 @@ namespace winrt::Microsoft::Windows::AppLifecycle::implementation
         return s_current.as<Microsoft::Windows::AppLifecycle::AppInstance>();
     }
 
-    IVector<Microsoft::Windows::AppLifecycle::AppInstance> AppInstance::GetInstances()
+    HRESULT AppInstance::GetInstancesImpl(IVector<Microsoft::Windows::AppLifecycle::AppInstance>& instancesOut) noexcept try
     {
         // Force the singleton init.
         GetCurrent();
@@ -338,6 +338,19 @@ namespace winrt::Microsoft::Windows::AppLifecycle::implementation
             }
         }
 
+        instancesOut = instances;
+        return S_OK;
+    }
+    CATCH_RETURN()
+
+    IVector<Microsoft::Windows::AppLifecycle::AppInstance> AppInstance::GetInstances()
+    {
+        // Delegate to the noexcept GetInstancesImpl worker and rethrow any failure
+        // HRESULT cleanly via wil::ResultException. This avoids the deep WIL
+        // FormatMessage-based exception logging chain that caused stack overflow on
+        // the hot path (Bug 61688595).
+        IVector<Microsoft::Windows::AppLifecycle::AppInstance> instances{ nullptr };
+        THROW_IF_FAILED(GetInstancesImpl(instances));
         return instances;
     }
 
diff --git a/dev/AppLifecycle/AppInstance.h b/dev/AppLifecycle/AppInstance.h
index beb02af484..325cd47eac 100644
--- a/dev/AppLifecycle/AppInstance.h
+++ b/dev/AppLifecycle/AppInstance.h
@@ -55,6 +55,12 @@ namespace winrt::Microsoft::Windows::AppLifecycle::implementation
         void EnqueueRedirectionRequestId(GUID id);
         GUID DequeueRedirectionRequestId();
 
+        // noexcept HRESULT-returning worker for GetInstances. The public GetInstances
+        // boundary is intentionally thin so a failed HRESULT does not trigger the deep
+        // C++/WinRT projection rethrow path that exhausted the stack via WIL's
+        // FormatMessage-based exception logging (Bug 61688595).
+        static HRESULT GetInstancesImpl(winrt::Windows::Foundation::Collections::IVector<Microsoft::Windows::AppLifecycle::AppInstance>& instancesOut) noexcept;
+
         // Named object prefixes used to scope.
         std::wstring m_moduleName;
         std::wstring m_processName;
diff --git a/dev/AppNotifications/AppNotificationManager.cpp b/dev/AppNotifications/AppNotificationManager.cpp
index bcee2ddfc5..71f0a3ea32 100644
--- a/dev/AppNotifications/AppNotificationManager.cpp
+++ b/dev/AppNotifications/AppNotificationManager.cpp
@@ -421,13 +421,8 @@ namespace winrt::Microsoft::Windows::AppNotifications::implementation
     }
     CATCH_RETURN()
 
-        void AppNotificationManager::Show(winrt::Microsoft::Windows::AppNotifications::AppNotification const& notification)
+    HRESULT AppNotificationManager::ShowImpl(winrt::Microsoft::Windows::AppNotifications::AppNotification const& notification) noexcept try
     {
-        if (!IsSupported())
-        {
-            return;
-        }
-
         auto logTelemetry{ AppNotificationTelemetry::Show::Start(
             g_telemetryHelper,
             m_appId,
@@ -436,21 +431,37 @@ namespace winrt::Microsoft::Windows::AppNotifications::implementation
             notification.Group(),
             winrt::AppNotificationConferencingConfig::IsCallingPreviewSupported()) };
 
-        THROW_HR_IF(WPN_E_NOTIFICATION_POSTED, notification.Id() != 0);
+        RETURN_HR_IF(WPN_E_NOTIFICATION_POSTED, notification.Id() != 0);
 
         winrt::com_ptr<::ABI::Microsoft::Internal::ToastNotifications::INotificationProperties> notificationProperties = winrt::make_self<NotificationProperties>(notification);
 
         winrt::com_ptr<::ABI::Microsoft::Internal::ToastNotifications::INotificationTransientProperties> notificationTransientProperties = winrt::make_self<NotificationTransientProperties>(notification);
 
         DWORD notificationId = 0;
-        THROW_IF_FAILED(ToastNotifications_PostToast(m_appId.c_str(), notificationProperties.get(), notificationTransientProperties.get(), &notificationId));
+        RETURN_IF_FAILED(ToastNotifications_PostToast(m_appId.c_str(), notificationProperties.get(), notificationTransientProperties.get(), &notificationId));
 
-        THROW_HR_IF(E_UNEXPECTED, notificationId == 0);
+        RETURN_HR_IF(E_UNEXPECTED, notificationId == 0);
 
         implementation::AppNotification* notificationImpl = get_self<implementation::AppNotification>(notification);
         notificationImpl->SetNotificationId(notificationId);
 
         logTelemetry.Stop();
+        return S_OK;
+    }
+    CATCH_RETURN()
+
+    void AppNotificationManager::Show(winrt::Microsoft::Windows::AppNotifications::AppNotification const& notification)
+    {
+        if (!IsSupported())
+        {
+            return;
+        }
+
+        // Delegate to the noexcept ShowImpl worker and rethrow any failure HRESULT
+        // cleanly via wil::ResultException. This avoids the deep WIL
+        // FormatMessage-based exception logging chain that caused stack overflow on
+        // the hot path (Bug 61688595).
+        THROW_IF_FAILED(ShowImpl(notification));
     }
 
     winrt::Windows::Foundation::IAsyncOperation<winrt::Microsoft::Windows::AppNotifications::AppNotificationProgressResult> AppNotificationManager::UpdateAsync(winrt::Microsoft::Windows::AppNotifications::AppNotificationProgressData const data, hstring const tag, hstring const group)
diff --git a/dev/AppNotifications/AppNotificationManager.h b/dev/AppNotifications/AppNotificationManager.h
index 7282fc0e59..09dfa8cfff 100644
--- a/dev/AppNotifications/AppNotificationManager.h
+++ b/dev/AppNotifications/AppNotificationManager.h
@@ -58,6 +58,12 @@ namespace winrt::Microsoft::Windows::AppNotifications::implementation
 
         void UnregisterHelper();
 
+        // noexcept HRESULT-returning worker for Show. The public Show boundary is
+        // intentionally thin so a failed HRESULT does not trigger the deep C++/WinRT
+        // projection rethrow path that exhausted the stack via WIL's FormatMessage-based
+        // exception logging (Bug 61688595).
+        HRESULT ShowImpl(winrt::Microsoft::Windows::AppNotifications::AppNotification const& notification) noexcept;
+
         wil::unique_com_class_object_cookie m_notificationComActivatorRegistration;
         wil::srwlock m_lock;
         winrt::event<NotificationActivationEventHandler> m_notificationHandlers;