DCOM连接配置问题

我创建了ExcelDllTest,ATL动态库,有一个ExcelDll组件!
配置(window xp)连本机测试:
    1 在DCOM配置新增了一个ExcelDll Class(APPID正确)
    2 然后选中DCOM配置,单击配置我的电脑
      在默认属性中勾选在此计算机上启用分布COM,身份验证级别无,默认模拟级别模拟
   3 COM安全设置,访问权限 编辑限制有两个用户ANONYMOUS LOGON,everyone,默认安全限制有self,SYSTEM
   启动权限 编辑限制有两个用户Administrators,everyone,默认 有三个用户Adminstrator ,interactive,system.
4. 选择我的COM组件ExcelDll Class单击右键-属性,
   常规-身份验证级别设置为无,标识设置为交互式用户我做了一个测试客服程序,
#import "E:\\1234\\ExcelDllTest\\Debug\\ExcelDllTest.dll" no_namespace
#pragma warning(push)
#pragma warning(disable : 4290)
const CLSID CLSID_ExcelDll = {0xC7241A41,0x2B2E,0x40D1,{0x96,0xBE,0xAA,0xF1,0x9E,0xBF,0xC3,0x51}};
const IID IID_IExcelDll = {0xDFDD2491,0x6154,0x4DD8,{0xBF,0x62,0x19,0xD4,0xF7,0xC6,0x79,0x74}};
void CreateExcel(IExcelDllPtr p,_bstr_t machine,COAUTHIDENTITY& id)
{ 
HRESULT hr=S_OK;
  COAUTHINFO author_info;
  COSERVERINFO server_info;
  MULTI_QI mqi[1];
  if (machine.length==0)
  {
  hr=p.CreateInstance(__uuidof(IExcelDll));
  if (FAILED(hr))
  _com_issue_error(hr);
  }
  else
  {
  ZeroMemory(&author_info,sizeof(author_info));
  author_info.dwAuthnSvc=RPC_C_AUTHN_WINNT;
  author_info.dwAuthzSvc=RPC_C_AUTHZ_NONE;
  author_info.dwImpersonationLevel=RPC_C_IMP_LEVEL_IMPERSONATE;
  author_info.dwCapabilities=EOAC_NONE;
  author_info.pAuthIdentityData=&id;
  ZeroMemory(&server_info,sizeof(server_info));
  server_info.pwszName=machine;
  server_info.pAuthInfo=&author_info;
      mqi[0].pIID=&IID_IExcelDll;
  mqi[0].pItf=static_cast<IUnknown*>(p);
  hr=CoCreateInstanceEx(CLSID_ExcelDll,NULL,CLSCTX_REMOTE_SERVER ,
  &server_info,1,mqi);//创建失败
  }
  if (FAILED(hr))
  {
 DWORD dd= ::GetLastError();//返回1008
    // _com_issue_error(hr);
  }
  else if(FAILED(mqi[0].hr))
  {
  hr=mqi[0].hr;
  p=NULL;
  }
  else 
  {
  p.Attach(reinterpret_cast<IExcelDll*>(mqi[0].pItf));
  }
}
int main(int arg,char* argv[])
{
HRESULT hr;
COAUTHIDENTITY author_id;
char user[64]={"pr74"};
char password[64]={"74"};
hr=::CoInitializeEx(NULL,COINIT_APARTMENTTHREADED);
     
if (FAILED(hr)) return 0;
ZeroMemory(&author_id,sizeof(author_id));
author_id.Flags=SEC_WINNT_AUTH_IDENTITY_ANSI;
author_id.User=reinterpret_cast<unsigned short*>(user);
author_id.UserLength=strlen(user); author_id.Password=reinterpret_cast<unsigned short*>(password);
author_id.PasswordLength=strlen(password);
IExcelDllPtr pr;
CreateExcel(pr,"pr74",author_id);
if (pr)
pr->AddFile("d:\\123.txt");
CoUninitialize();
return 1;
}测试连接老是失败,请高手帮忙解决,初学COM