static extern IntPtr SetWinEventHook(WinEvents eventMin, WinEvents eventMax, IntPtr

    <System.Runtime.InteropServices.DllImport("user32.dll", EntryPoint:="SetWinEventHook")> _

    Private Shared Function SetWinEventHook( _

When you use a Win32 API that has a callback in managed code, such as SetWinEventHook, you should use GCHandle class structure to avoid exceptions.