钩子函数在xp可以运行，win7不行，如何改

钩子函数在xp可以运行，win7不行，怎么改？
//---------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

HHOOK hkb = NULL;

LRESULT CALLBACK keyboardProc(int ncode, WPARAM wparam,
              LPARAM lparam)
{
  DWORD flag = ((DWORD)lparam&0x40000000);
  if(flag &&(HC_ACTION == ncode))
  {
   char keyname[2];
   ZeroMemory(keyname,2);
    switch(wparam)
    {
    case VK_ESCAPE:
       Form1->Button1->Name = "ESC";
       break;
    }
   return CallNextHookEx(hkb, ncode, wparam, lparam);
  }
}
//---------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------

void __fastcall TForm1::Button1Click(TObject *Sender)
{
   hkb = SetWindowsHookEx(WH_KEYBOARD,
        (HOOKPROC)keyboardProc, HInstance, 0);

}
//---------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
  UnhookWindowsHookEx(hkb);
}
//---------------------------------------

小弟初学，什么都不懂，求大虾指教！

[最优解释]
使用WH_KEYBOARD_LL代替  WH_KEYBOARD
hkb = SetWindowsHookEx(WH_KEYBOARD_LL,(HOOKPROC)keyboardProc, HInstance, 0);     //win7 64位 ok

LRESULT CALLBACK keyboardProc(int ncode, WPARAM wparam,
   LPARAM lparam)
{
   //DWORD flag = ((DWORD)lparam&0x40000000);
   DWORD flag = ((DWORD)lparam );
   KBDLLHOOKSTRUCT   *pkbhs;

   if(flag &&(HC_ACTION == ncode))
   {
        //char keyname[2];
        //ZeroMemory(keyname,2);

        pkbhs   =   (KBDLLHOOKSTRUCT*)lparam;
        if   (pkbhs->vkCode==VK_ESCAPE ) Form1->Button1->Caption = "ESC";
        return CallNextHookEx(hkb, ncode, wparam, lparam);
   }
}
[其他解释]
谢谢，修改后可以用了，太感谢你了 
[其他解释]
如何改？