SetWinEventHook Only Hitting Callback After Application Start

I have this class that listens when the CTRL + ALT + DEL screen is displayed. When I run my application, it only runs once, after which the callback never hits again. Sometimes it causes memory leak giving me System.AccessViolationException

. I know this exception is related to this hook because when I remove the hook code it never raises those exceptions.

What am I doing wrong? Why would he only do the callback once?

public static void StartListeningForDesktopSwitch()
{
    SetWinEventHook(EVENT_SYSTEM_DESKTOPSWITCH, EVENT_SYSTEM_DESKTOPSWITCH,
        IntPtr.Zero, EventCallback, 0, 0, WINEVENT_OUTOFCONTEXT | WINEVENT_SKIPOWNTHREAD);
}

public static void EventCallback(IntPtr hWinEventHook, uint eventType,
    IntPtr hwnd, int idObject, int idChild, uint dwEventThread, uint dwmsEventTime)
{
    //do stuff when secure desktop is shown or hidden
    Log.LogEvent("Info", "Secure Desktop Event", "", "", null);
}

public delegate void WinEventDelegate(IntPtr hWinEventHook, uint eventType,
    IntPtr hwnd, int idObject, int idChild, uint dwEventThread, uint dwmsEventTime);


[DllImport("user32.dll")]
static extern IntPtr SetWinEventHook(uint eventMin, uint eventMax, IntPtr
        hmodWinEventProc, WinEventDelegate lpfnWinEventProc, uint idProcess,
    uint idThread, uint dwFlags);

const uint WINEVENT_OUTOFCONTEXT = 0x0000;
const uint WINEVENT_SKIPOWNTHREAD = 0x0001;
const uint EVENT_SYSTEM_DESKTOPSWITCH = 0x0020;

      

        
        
        
      

    

I am calling this static class from Main () like this:

WindowEventHook.StartListeningForDesktopSwitch();