[Guid("7127696E-AB87-427a-BC85-AB3CBA301CF3")]
[ClassInterface(ClassInterfaceType.AutoDual)]
[ComVisible(true)]

        [ComRegisterFunction]
        public static void RegisterFunction(Type type)
        {
            // Add the "Programmable" registry key under CLSID
            Registry.ClassesRoot.CreateSubKey(
                GetCLSIDSubKeyName(type, "Programmable"));

            // Register the full path to mscoree.dll which makes Excel happier.
            RegistryKey key = Registry.ClassesRoot.OpenSubKey(
                GetCLSIDSubKeyName(type, "InprocServer32"), true);
            key.SetValue("",
                System.Environment.SystemDirectory + @"\mscoree.dll",
                RegistryValueKind.String);
        }

        [ComUnregisterFunction]
        public static void UnregisterFunction(Type type)
        {
            // Remove the "Programmable" registry key under CLSID
            Registry.ClassesRoot.DeleteSubKey(
                GetCLSIDSubKeyName(type, "Programmable"), false);
        }

        private static string GetCLSIDSubKeyName(Type type, string subKeyName)
        {
            System.Text.StringBuilder s = new System.Text.StringBuilder();
            s.Append(@"CLSID\{");
            s.Append(type.GUID.ToString().ToUpper());
            s.Append(@"}\");
            s.Append(subKeyName);
            return s.ToString();
        }