C# FindWondow not recognized

[funkmonkey]

Hi. I'm having issues with FindWondow not being recognized in the code. I have not programmed in C++/C# for over 20 years, all of my recent programming has been in VBA. I have found code which I cludged together and the only issue is the FindWindow not being recognized even though it is defined correctly. Any input would be very helpful.

using System;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Timers;

//public bool bTimerOn = FALSE;
//public unsigned long ulWait = ullWait;


namespace VbaEventEPIQspace
{
    [InterfaceType(ComInterfaceType.InterfaceIsIDispatch)]
    [Guid("EB2637FE-E07F-4071-8472-B531030FD6B7")]
    //[InterfaceType(ComInterfaceType.InterfaceIsDual)]
    public interface _DEventInterface
    {

        [DispId(1)]
        void EPIQ_Init(long lWait);

        [DispId(2)]
        void EPIQ_StartTimer();

        [DispId(3)]
        void EPIQ_StopTimer();

        [DispId(4)]
        void EPIQ_SetTimer();

        [DispId(5)]
        void EPIQ_ExecuteProc();

    }

    [ProgId("EPIQ_Utils.Utils")]
    [ComSourceInterfaces(typeof(_DEventInterface))]
    [Guid("9BAED3EE-BB01-4605-9C22-EEAE5BA7141B")]
    [ClassInterface(ClassInterfaceType.AutoDual)]
    [ComVisible(true)]




    public class EPIQ_Utils
    {
 //       bool bTimerOn;
 //       long lWait;
        const int BM_CLICK = 0xF5;
        private static Timer timer;

        //MessageBox(NULL, (LPCWSTR)"Made it here", (LPCWSTR)"We made it", NULL);
        [DllImport("user32.dll")] 
        public static extern int FindWindow(string lpClassName, String lpWindowName);

        [DllImport("user32.dll")]
        public static extern int SendMessage(IntPtr hWnd, int wMsg, IntPtr wParam, IntPtr lParam);

        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        static extern IntPtr FindWindowEx(IntPtr parentHandle, IntPtr childAfter, string lclassName, string windowTitle);

        [DllImport("user32.dll")]
        private static extern IntPtr SetActiveWindow(IntPtr hwnd);

        public EPIQ_Utils()
        {
            timer = new System.Timers.Timer();
            timer.Interval = 1000;
            timer.Elapsed += OnTimerEvent;
            timer.AutoReset = true;
            timer.Enabled = false;
        }
        private void OnTimerEvent(object source, System.Timers.ElapsedEventArgs e) 
        { 
            //create two structures to hold our Main Window handle
            //and the Button's handle
            IntPtr WindowHandle;
            IntPtr ButtonHandle;

            //this window's caption is "File Download", so we search for it's handle using the FindWindow API		
            WindowHandle = FindWindow(null, "Message from webpage");

            SetActiveWindow(WindowHandle);

            //the Button's Caption is "OK" and it is a "Button".  SPYXX.exe that comes with Microsoft Visual Studio will reveal this information to you
            ButtonHandle = FindWindowEx(WindowHandle, IntPtr.Zero, "Button", "OK");

            //send a message to the button that you are "clicking" it.  Surprisingly C++ understands what BM_CLICK is without having to set it.  Different than VB
            SendMessage(ButtonHandle, BM_CLICK, IntPtr.Zero, IntPtr.Zero);

        }






 //           void EPIQ_InitializeTimer(long ltime)
 //           {
                
 //           }

 //       void EPIQ_SetTimer() 
 //       {
 //           if (bTimerOn)
 //           {

 //           }
         
 //      }

 //       void EPIQ_ExecuteProc()
 //       {
 //           if (bTimerOn)
 //           {
 //               TimerProc;
 //               EPIQ_SetTimer;

 //           }
 //       }

 //       void EPIQ_StopTimer()
 //       {
 //           bTimerOn = false;
 //       }
    }
}

[VictorN]

I have found code which I cludged together and the only issue is the FindWindow not being recognized even though it is defined correctly.

What line in your code snippet produces this error message?