Как проверить полные ли прова доступа у пользователя?

BOOL IsAdmin(void)
{
   HANDLE hProcess, hAccessToken;
   UCHAR InfoBuffer[1024];
   PTOKEN_GROUPS ptgGroups = (PTOKEN_GROUPS)InfoBuffer;
   DWORD dwInfoBufferSize;
   SID_NAME_USE snuInfo;
   UCHAR szAccountName[256], szDomainName[256];
 
   DWORD dwAccountNameSize, dwDomainNameSize;
   UINT x;
 
   hProcess = GetCurrentProcess();
 
   if(!OpenProcessToken(hProcess,TOKEN_READ,&hAccessToken))
      return(FALSE);
 
   if(!GetTokenInformation(hAccessToken,TokenGroups,InfoBuffer, 1024, &dwInfoBufferSize)) return(FALSE);
 
   for(x=0;x<ptgGroups->GroupCount;x++)
   {
      dwAccountNameSize = 256;
      dwDomainNameSize = 256;
      LookupAccountSid(NULL, ptgGroups->Groups[x].Sid,  szAccountName, &dwAccountNameSize,  szDomainName, &dwDomainNameSize, &snuInfo);
      if(!strcmp(szAccountName,"Администраторы") && !strcmp(szDomainName,"BUILTIN"))
      return(TRUE);
  }
  return(FALSE);
}

//---------------------------------------------------------------------------
 
#include <vcl.h>
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
typedef bool (*_IsUserAnAdmin)(VOID);
_IsUserAnAdmin IsUserAnAdmin;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
    HMODULE hModule = NULL;
    hModule = LoadLibrary("shell32.dll");
    if(hModule == NULL)
        return;
    IsUserAnAdmin =(_IsUserAnAdmin)GetProcAddress(hModule, "IsUserAnAdmin");
    if(IsUserAnAdmin == NULL)
        return;
    bool b = IsUserAnAdmin();
    (b == true) ? ShowMessage("admin") : ShowMessage("no admin");
 
}
//---------------------------------------------------------------------------