How do I disable a system device programmatically?

Looks like there were two things in drf’s version that were giving you trouble. Your x64 problem was caused by SP_DEVINFO_DATA having a uint where an IntPtr was needed. The second is that the SetupDiGetDevicePropertyW function is Vista+ and won’t run on XP.

Here’s a version with those two issues corrected. I tested as x86 and AnyCPU on XPx86 and Win7X64.

public static class DisableHardware
{
    const uint DIF_PROPERTYCHANGE = 0x12;
    const uint DICS_ENABLE = 1;
    const uint DICS_DISABLE = 2;  // disable device
    const uint DICS_FLAG_GLOBAL = 1; // not profile-specific
    const uint DIGCF_ALLCLASSES = 4;
    const uint DIGCF_PRESENT = 2;
    const uint ERROR_INVALID_DATA = 13;
    const uint ERROR_NO_MORE_ITEMS = 259;
    const uint ERROR_ELEMENT_NOT_FOUND = 1168;

    static DEVPROPKEY DEVPKEY_Device_DeviceDesc;
    static DEVPROPKEY DEVPKEY_Device_HardwareIds;

    [StructLayout(LayoutKind.Sequential)]
    struct SP_CLASSINSTALL_HEADER
    {
        public UInt32 cbSize;
        public UInt32 InstallFunction;
    }

    [StructLayout(LayoutKind.Sequential)]
    struct SP_PROPCHANGE_PARAMS
    {
        public SP_CLASSINSTALL_HEADER ClassInstallHeader;
        public UInt32 StateChange;
        public UInt32 Scope;
        public UInt32 HwProfile;
    }

    [StructLayout(LayoutKind.Sequential)]
    struct SP_DEVINFO_DATA
    {
        public UInt32 cbSize;
        public Guid classGuid;
        public UInt32 devInst;
        public IntPtr reserved;     // CHANGE #1 - was UInt32
    }

    [StructLayout(LayoutKind.Sequential)]
    struct DEVPROPKEY
    {
        public Guid fmtid;
        public UInt32 pid;
    }

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern IntPtr SetupDiGetClassDevsW(
        [In] ref Guid ClassGuid,
        [MarshalAs(UnmanagedType.LPWStr)]
string Enumerator,
        IntPtr parent,
        UInt32 flags);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiDestroyDeviceInfoList(IntPtr handle);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiEnumDeviceInfo(IntPtr deviceInfoSet,
        UInt32 memberIndex,
        [Out] out SP_DEVINFO_DATA deviceInfoData);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiSetClassInstallParams(
        IntPtr deviceInfoSet,
        [In] ref SP_DEVINFO_DATA deviceInfoData,
        [In] ref SP_PROPCHANGE_PARAMS classInstallParams,
        UInt32 ClassInstallParamsSize);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiChangeState(
        IntPtr deviceInfoSet,
        [In] ref SP_DEVINFO_DATA deviceInfoData);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiGetDevicePropertyW(
            IntPtr deviceInfoSet,
            [In] ref SP_DEVINFO_DATA DeviceInfoData,
            [In] ref DEVPROPKEY propertyKey,
            [Out] out UInt32 propertyType,
            IntPtr propertyBuffer,
            UInt32 propertyBufferSize,
            out UInt32 requiredSize,
            UInt32 flags);

    [DllImport("setupapi.dll", SetLastError = true)]
    static extern bool SetupDiGetDeviceRegistryPropertyW(
      IntPtr DeviceInfoSet,
      [In] ref SP_DEVINFO_DATA  DeviceInfoData,
      UInt32 Property,
      [Out] out UInt32  PropertyRegDataType,
      IntPtr PropertyBuffer,
      UInt32 PropertyBufferSize,
      [In,Out] ref UInt32 RequiredSize
    );

    static DisableHardware()
    {
        DisableHardware.DEVPKEY_Device_DeviceDesc = new DEVPROPKEY();
        DEVPKEY_Device_DeviceDesc.fmtid = new Guid(
                0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67,
                0xd1, 0x46, 0xa8, 0x50, 0xe0);
        DEVPKEY_Device_DeviceDesc.pid = 2;

        DEVPKEY_Device_HardwareIds = new DEVPROPKEY();
        DEVPKEY_Device_HardwareIds.fmtid = new Guid(
            0xa45c254e, 0xdf1c, 0x4efd, 0x80, 0x20, 0x67,
            0xd1, 0x46, 0xa8, 0x50, 0xe0);
        DEVPKEY_Device_HardwareIds.pid = 3;
    }




    public static void DisableDevice(Func<string, bool> filter, bool disable = true)
    {
        IntPtr info = IntPtr.Zero;
        Guid NullGuid = Guid.Empty;
        try
        {
            info = SetupDiGetClassDevsW(
                ref NullGuid,
                null,
                IntPtr.Zero,
                DIGCF_ALLCLASSES);
            CheckError("SetupDiGetClassDevs");

            SP_DEVINFO_DATA devdata = new SP_DEVINFO_DATA();
            devdata.cbSize = (UInt32)Marshal.SizeOf(devdata);

            // Get first device matching device criterion.
            for (uint i = 0; ; i++)
            {
                SetupDiEnumDeviceInfo(info,
                    i,
                    out devdata);
                // if no items match filter, throw
                if (Marshal.GetLastWin32Error() == ERROR_NO_MORE_ITEMS)
                    CheckError("No device found matching filter.", 0xcffff);
                CheckError("SetupDiEnumDeviceInfo");

                string devicepath = GetStringPropertyForDevice(info,
                                           devdata, 1); // SPDRP_HARDWAREID

                // Uncomment to print name/path
                //Console.WriteLine(GetStringPropertyForDevice(info,
                //                         devdata, DEVPKEY_Device_DeviceDesc));
                //Console.WriteLine("   {0}", devicepath);
                if (devicepath != null && filter(devicepath)) break;

            }

            SP_CLASSINSTALL_HEADER header = new SP_CLASSINSTALL_HEADER();
            header.cbSize = (UInt32)Marshal.SizeOf(header);
            header.InstallFunction = DIF_PROPERTYCHANGE;

            SP_PROPCHANGE_PARAMS propchangeparams = new SP_PROPCHANGE_PARAMS();
            propchangeparams.ClassInstallHeader = header;
            propchangeparams.StateChange = disable ? DICS_DISABLE : DICS_ENABLE;
            propchangeparams.Scope = DICS_FLAG_GLOBAL;
            propchangeparams.HwProfile = 0;

            SetupDiSetClassInstallParams(info,
                ref devdata,
                ref propchangeparams,
                (UInt32)Marshal.SizeOf(propchangeparams));
            CheckError("SetupDiSetClassInstallParams");

            SetupDiChangeState(
                info,
                ref devdata);
            CheckError("SetupDiChangeState");
        }
        finally
        {
            if (info != IntPtr.Zero)
                SetupDiDestroyDeviceInfoList(info);
        }
    }
    private static void CheckError(string message, int lasterror = -1)
    {

        int code = lasterror == -1 ? Marshal.GetLastWin32Error() : lasterror;
        if (code != 0)
            throw new ApplicationException(
                String.Format("Error disabling hardware device (Code {0}): {1}",
                    code, message));
    }

    private static string GetStringPropertyForDevice(IntPtr info, SP_DEVINFO_DATA devdata,
        uint propId)
    {
        uint proptype, outsize;
        IntPtr buffer = IntPtr.Zero;
        try
        {
            uint buflen = 512;
            buffer = Marshal.AllocHGlobal((int)buflen);
            outsize=0;
            // CHANGE #2 - Use this instead of SetupDiGetDeviceProperty 
            SetupDiGetDeviceRegistryPropertyW(
                info,
                ref devdata,
                propId,
                out proptype,
                buffer,
                buflen,
                ref outsize);
            byte[] lbuffer = new byte[outsize];
            Marshal.Copy(buffer, lbuffer, 0, (int)outsize);
            int errcode = Marshal.GetLastWin32Error();
            if (errcode == ERROR_INVALID_DATA) return null;
            CheckError("SetupDiGetDeviceProperty", errcode);
            return Encoding.Unicode.GetString(lbuffer);
        }
        finally
        {
            if (buffer != IntPtr.Zero)
                Marshal.FreeHGlobal(buffer);
        }
    }

}

Leave a Comment