This is a simple program that Enable/Disable USB ports on a PC. A USB port is a standard cable connection interface for personal computers and consumer electronics devices. USB stands for Universal Serial Bus, an industry standard for short-distance digital data communications.

Code:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Runtime.InteropServices;
using Microsoft.Win32;
using System.Threading;
using System.Windows.Forms;

namespace USBEnableDisable
{
    public partial class frmMain : Form
    {
        public frmMain()
        {
            InitializeComponent();
        }
        RegistryKey Regkey, RegKey2;
        Int32 rValue,rsvalue,Gvalue,tvalue;
        string Regpath = "System\\CurrentControlSet\\Services\\USBSTOR";
        string ReadAndWriteRegPath2 = "System\\CurrentControlSet\\Control";
        string ReadAndWriteRegPath = "System\\CurrentControlSet\\Control\\StorageDevicePolicies";
        
      

        private void RadioButtondisable_CheckedChanged(object sender, EventArgs e)
        {
            GroupBox2.Enabled = false;
             rValue = 4;
        }

        private void RadioButtonenable_CheckedChanged(object sender, EventArgs e)
        {
            GroupBox2.Enabled = true;
             rValue = 3;
        }

        private void RadioButtonreadonly_CheckedChanged(object sender, EventArgs e)
        {
            rsvalue = 1;
        }

        private void btnOK_Click(object sender, EventArgs e)
        {
            Regkey = Registry.LocalMachine.OpenSubKey(Regpath, true);
            Regkey.SetValue("Start", rValue);
            if (GroupBox2.Enabled == true)
            {
                RegKey2 = Registry.LocalMachine.OpenSubKey(ReadAndWriteRegPath2, true);
                RegKey2.CreateSubKey("StorageDevicePolicies");
                RegKey2 = Registry.LocalMachine.OpenSubKey(ReadAndWriteRegPath, true);
                RegKey2.SetValue("WriteProtect", rsvalue);
            }
            if ((rValue == 3) && (rsvalue == 1))
            {
                MessageBox.Show("USB Port were enable and Read only is enabled");
            }
            else if ((rValue == 3) && (rsvalue == 0))
            {
                MessageBox.Show("USB Port were enable and Read and write is enabled");
            }
            else
            {
                MessageBox.Show("USB Port were disable");
            }
        }

        private void frmMain_Load(object sender, EventArgs e)
        {
            isAdmin = IsUserAnAdmin();
            if (isAdmin == false)
            {
                MessageBox.Show("You don't have proper privileges level to make changes, administrators privileges are required", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                Close();
            }
            else
            {
                Regkey = Registry.LocalMachine.OpenSubKey(Regpath, true);
                Gvalue = Convert.ToInt32(Regkey.GetValue("Start"));
                //check the current state of the usb/whether is enabled or disabled
                if (Gvalue == 3)
                {
                    rdoEnable.Checked = true;
                }
                else if (Gvalue == 4)
                {
                    rdoDisable.Checked = true;
                }
                RegKey2 = Registry.LocalMachine.OpenSubKey(ReadAndWriteRegPath, true);
                try
                {
                    tvalue = Convert.ToInt32(RegKey2.GetValue("WriteProtect"));
                    if (tvalue == 1)
                    {
                        RadioButtonreadonly.Checked = true;
                    }
                    else if (tvalue == 0)
                    {
                        RadioButtonreadwrite.Checked = true;
                    }
                }
                catch (NullReferenceException) { }
            }
        }

        private void btnCancel_Click(object sender, EventArgs e)
        {
            Close();
        }

        private void RadioButtonreadwrite_CheckedChanged(object sender, EventArgs e)
        {
            rsvalue = 0;
        }
        bool isAdmin;
        [DllImport ("shell32")]
        static extern bool  IsUserAnAdmin();
 
    }
}