diff --git a/src/Shmuelie.WinRTServer/NativeMethods.txt b/src/Shmuelie.WinRTServer/NativeMethods.txt
index 1aaebe3..a267404 100644
--- a/src/Shmuelie.WinRTServer/NativeMethods.txt
+++ b/src/Shmuelie.WinRTServer/NativeMethods.txt
@@ -21,4 +21,5 @@ RoInitialize
 RoRegisterActivationFactories
 RoRevokeActivationFactories
 S_FALSE
-GLOBALOPT_RO_FLAGS
\ No newline at end of file
+GLOBALOPT_RO_FLAGS
+WindowsGetStringRawBuffer
\ No newline at end of file
diff --git a/src/Shmuelie.WinRTServer/WinRtServer.cs b/src/Shmuelie.WinRTServer/WinRtServer.cs
index 2750332..a45b438 100644
--- a/src/Shmuelie.WinRTServer/WinRtServer.cs
+++ b/src/Shmuelie.WinRTServer/WinRtServer.cs
@@ -183,7 +183,7 @@ private unsafe HRESULT ActivationFactoryCallback(HSTRING activatableClassId, IAc
             return HRESULT.E_INVALIDARG;
         }
 
-        if (!factories.TryGetValue(activatableClassId.ToString(), out BaseActivationFactory? managedFactory))
+        if (!factories.TryGetValue(activatableClassId.AsString(), out BaseActivationFactory? managedFactory))
         {
             factory = null;
             return HRESULT.E_NOINTERFACE;
diff --git a/src/Shmuelie.WinRTServer/Windows/winrt/HSTRING.cs b/src/Shmuelie.WinRTServer/Windows/winrt/HSTRING.cs
new file mode 100644
index 0000000..8aceb19
--- /dev/null
+++ b/src/Shmuelie.WinRTServer/Windows/winrt/HSTRING.cs
@@ -0,0 +1,24 @@
+using Windows.Win32.Foundation;
+using Windows.Win32.System.WinRT;
+using static Windows.Win32.PInvoke;
+
+namespace Shmuelie.Interop.Windows;
+
+internal static class HSTRING_
+{
+#if !NETSTANDARD
+    [System.Runtime.Versioning.SupportedOSPlatform("windows8.0")]
+#endif
+    public unsafe static string AsString(this HSTRING @this)
+    {
+        if (@this.IsNull)
+        {
+            return string.Empty;
+        }
+
+        uint characterCount;
+        PCWSTR characters = WindowsGetStringRawBuffer(@this, &characterCount);
+
+        return characters.ToString();
+    }
+}