驱动加载后又马上被卸载了解决方案

驱动加载后又马上被卸载了
我现在学习流驱动，写了一个空的驱动，驱动是编进内核了，但加载了，马上又被卸载了，超级终端输出为

GPI DLL_PROCESS_ATTACH
GPI DLL_PROCESS_DETACH

我写了一个测试程序，GetLastError返回值为55，

驱动源码如下：
// GPI.cpp : Defines the entry point for the DLL application.
//

#include "stdafx.h"

BOOL APIENTRY DllMain( HANDLE hModule, 
  DWORD ul_reason_for_call, 
  LPVOID lpReserved
  )
{
 switch(ul_reason_for_call)  
  {  
  case DLL_PROCESS_ATTACH:
  RETAILMSG(1,(TEXT("GPI DLL_PROCESS_ATTACH\n")));
  return TRUE;  
  case DLL_THREAD_ATTACH:  
  RETAILMSG(1,(TEXT("GPI DLL_THEARD_ATTACH\n")));  
  return TRUE;  
  case DLL_PROCESS_DETACH:  
  RETAILMSG(1,(TEXT("GPI DLL_PROCESS_DETACH\n")));  
  return TRUE;  
  case DLL_THREAD_DETACH:  
  RETAILMSG(1,(TEXT("GPI DLL_THEARD_DETACH\n")));  
  return TRUE;
  }
}

DWORD GPI_Init(DWORD dwContext)
{
 DWORD dwRet=0;  
 RETAILMSG(1,(TEXT("GPI Init\n\r")));  
 dwRet=1;  
 return dwRet;
}

BOOL GPI_Deinit(DWORD dwContext)
{
 RETAILMSG(1,(TEXT("GPI Deinit\n\r")));  
  return true;
}

DWORD GPI_Open(DWORD dwContext)
{


 RETAILMSG(1,(TEXT("GPI Open\n\r")));  
  return true;
}
BOOL GPI_Close(DWORD dwContext)
{
 RETAILMSG(1,(TEXT("GPI Close\n\r")));  
  return true;
}



[解决办法]
55:指定网络资源或设备不再可用
驱动应该没加载成功
[解决办法]
5.0 还是 6.0 
检查下 注册表，跟bib文件
[解决办法]
用驱动调试助手看看
[解决办法]
驱动加载又卸载也可能与驱动的def文件有关