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[DllImport("setupapi.dll", CharSet = CharSet.Auto)]
        static extern IntPtr SetupDiGetClassDevs(           // 1st form using a ClassGUID
           ref Guid ClassGuid,
           int Enumerator,
           IntPtr hwndParent,
           int Flags
        );
        [DllImport("setupapi.dll", CharSet = CharSet.Auto)]     // 2nd form uses an Enumerator
        static extern IntPtr SetupDiGetClassDevs(
           int ClassGuid,
           string Enumerator,
           IntPtr hwndParent,
           int Flags
        );


        private const int DIGCF_PRESENT = (0x00000002);

        private const int DN_DISABLEABLE = (0x00002000); // Can be rebalance
        private const int CM_PROB_HARDWARE_DISABLED = (0x0000001D); // device disabled
        private const int DN_HAS_PROBLEM = (0x00000400); // Need device installe
        private const int CM_PROB_DISABLED = (0x00000016); // devinst is disable

        private const int DIF_PROPERTYCHANGE = (0x00000012);
        private const int DICS_FLAG_GLOBAL = (0x00000001); // make change in all hardware profile

        private const int DICS_ENABLE = (0x00000001);
        private const int DICS_DISABLE = (0x00000002);
        private const int DICS_PROPCHANGE = (0x00000003);
        private const int DICS_START = (0x00000004);
        private const int DICS_STOP = (0x00000005);

        [DllImport(@"setupapi.dll", CharSet = CharSet.Auto, SetLastError = true)]
        public static extern bool SetupDiDestroyDeviceInfoList(IntPtr hDevInfo);

        [DllImport("setupapi.dll")]
        private static extern bool
        SetupDiEnumDeviceInfo(IntPtr p_DeviceInfoSet, UInt32 ui_MemberIndex,
        SP_DEVINFO_DATA o_DeviceInfoData);

        [DllImport("setupapi.dll", SetLastError = true, CharSet = CharSet.Auto)]
        public static extern bool SetupDiSetClassInstallParams(
        IntPtr DeviceInfoSet, IntPtr DeviceInfoData,
        IntPtr ClassInstallParams, int ClassInstallParamsSize);

        [StructLayout(LayoutKind.Sequential)]
        private class SP_DEVINFO_DATA
        {
            public int cbSize;
            public Guid ClassGuid;
            public int DevInst; // DEVINST handl
            public ulong Reserved;
        }

        [StructLayout(LayoutKind.Sequential)]
        public struct SP_CLASSINSTALL_HEADER
        {
            public int cbSize;
            public uint InstallFunction;
        }


        [StructLayout(LayoutKind.Sequential)]
        public struct SP_PROPCHANGE_PARAMS
        {
            public SP_CLASSINSTALL_HEADER ClassInstallHeader;
            public uint StateChange;
            public uint Scope;
            public uint HwProfile;
        }


        //..

        private static void StateChange(uint ui_NewState, uint ui_SelectedItem, IntPtr p_DeviceInfoSet)
        {
            SP_DEVINFO_DATA o_DeviceInfoData = new SP_DEVINFO_DATA();
            bool b_Res = false;
            SP_PROPCHANGE_PARAMS o_PropChangeParams = new SP_PROPCHANGE_PARAMS();
            int i_PCPSize = 0;
            IntPtr p_PropChangeParams;
            int i_DIDSize = 0;
            IntPtr p_DeviceInfoData;

            o_DeviceInfoData.cbSize = 28;
            //is devices exist for clas
            o_DeviceInfoData.DevInst = 0;
            o_DeviceInfoData.ClassGuid = Guid.Empty;
            o_DeviceInfoData.Reserved = 0;

            Guid dgg = new Guid("{4D36E967-E325-11CE-BFC1-08002BE10318}");
            IntPtr hDevInfo1 = SetupDiGetClassDevs(ref dgg, 0, IntPtr.Zero, DIGCF_PRESENT);

            b_Res = SetupDiEnumDeviceInfo(hDevInfo1,
            ui_SelectedItem, o_DeviceInfoData);
            if (b_Res == false)
            { //no such device
                SetupDiDestroyDeviceInfoList(p_DeviceInfoSet);
                throw new ApplicationException("Device Does Not Exist.");


                o_PropChangeParams.ClassInstallHeader.InstallFunction = DIF_PROPERTYCHANGE;
                o_PropChangeParams.ClassInstallHeader.cbSize = Marshal.SizeOf(typeof(SP_CLASSINSTALL_HEADER));
                o_PropChangeParams.StateChange = ui_NewState;
                o_PropChangeParams.Scope = Convert.ToUInt32(DICS_FLAG_GLOBAL);
                o_PropChangeParams.HwProfile = 0;
                i_PCPSize = Marshal.SizeOf(o_PropChangeParams);

                p_PropChangeParams = Marshal.AllocHGlobal(i_PCPSize);
                Marshal.StructureToPtr(o_PropChangeParams, p_PropChangeParams, true);
                i_DIDSize = Marshal.SizeOf(o_DeviceInfoData);
                p_DeviceInfoData = Marshal.AllocHGlobal(i_DIDSize);
                Marshal.StructureToPtr(o_DeviceInfoData, p_DeviceInfoData, true);

                b_Res = SetupDiSetClassInstallParams(p_DeviceInfoSet, p_DeviceInfoData,
                p_PropChangeParams, i_PCPSize);
                Marshal.FreeHGlobal(p_PropChangeParams);
                Marshal.FreeHGlobal(p_DeviceInfoData);
                if (b_Res == false)
                {
                    SetupDiDestroyDeviceInfoList(p_DeviceInfoSet);
                }

            }




        }