_ConnectionPtr m_pConnection;
    //   创建到Master数据库的连接   ，注意是master数据库
    try
    {
    //   创建Connection对象
    m_pConnection.CreateInstance( "ADODB.Connection");
    //   设置连接字符串，必须是BSTR型或者_bstr_t类型
    _bstr_t   strMasterConnect="Provider=SQLOLEDB; Server="+databaseip+";Database=master; uid=sa; pwd=sa;";
    //        _bstr_t   strMasterConnect="Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=master;Data Source="+databaseip+"";
    //        _bstr_t   strMasterConnect=str;
    m_pConnection-> Open(strMasterConnect, "", "",adModeUnknown);
    }
    //   捕捉异常
    catch(_com_error   e)
    {
    //   显示错误信息
    m_pConnection->Close();
    m_pConnection=NULL;
    AfxMessageBox(e.Description());
    return 0;
    }

    TCHAR szPath3[MAX_PATH];
    strcpy( szPath3, szPath2 );
    strcat( szPath3, "\\*.bak" );
    CFileDialog   dlg(FALSE,"",szPath3,OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,"(*.bak)|*.bak|",NULL);
    if(dlg.DoModal()!=IDOK)
    return 0;
    m_file=dlg.GetPathName();
    str3=dlg.GetFileName();
    int findindex=FindingString(m_file.GetBuffer(0),str3.GetBuffer(0),0);
    str5.Empty();
    for(i=0;i<findindex;i++)
    {
    str5+=m_file.GetAt(i);
    }
    str3=dlg.GetFileName();
    str4.Empty();
    for(i=0;i<str3.GetLength()-4;i++)
    {
    str4+=str3.GetAt(i);
    }
//    str3.Format("%s\\",szPath2);
    str3=str5;
    str3+=str4;
    str6.Empty();
    for(i=0;i<str5.GetLength()-1;i++)
    str6+=str5.GetAt(i);
    str8=str6;
    findindex=FindingString(str6.GetBuffer(0),"\\",0);
    if(findindex<0)
    {
        str6="bakeup";
        AfxMessageBox("请选择备份文件夹!");
        return 0;
    }
    while(findindex>=0)
    {
        str7.Empty();
        for(i=findindex+1;i<str6.GetLength();i++)
        str7+=str6.GetAt(i);
        str6=str7;
        findindex=FindingString(str6.GetBuffer(0),"\\",0);
    }
  CPasswordDlg PasswordDlg;
    if(PasswordDlg.DoModal()!=IDOK)
    {
        m_pConnection->Close();
        m_pConnection=NULL;
        m_com.OnInitADOConn();
        return 0;
    }
    CWiCNet* pNetFunctionCaller = new CWiCNet;
    strcpy( szPath2, str8.GetBuffer(0) );
    while(!pNetFunctionCaller->NetShareAdd( szPath2, str6.GetBuffer(0), "", 0, "") )
    {
    pNetFunctionCaller->NetShareDel(str6.GetBuffer(0));
//    pNetFunctionCaller->NetShareAdd(szPath2, "bakeup", "", 0, "");
    }
    char   UserName[255];   
    unsigned long a=255;
    GetUserName(UserName, &a);  
    str.Format("%s",UserName);
    str1.Empty();
    CString strhost;
    char szHostName[200];    
    //获得主机名
    gethostname( szHostName, strlen( szHostName ) );
    strhost.Format("%s",szHostName);
    str1=PasswordDlg.m_str;
    try
    {
    vSQL="xp_cmdshell 'net use \\\\"+localip+"\\"+str6+" "+str1+"/user:"+strhost+"\\"+str+"'";//str1为计算机登录密码，str为计算机登录用户名，strhost为计算机名

    m_pConnection-> Execute(vSQL,NULL,adCmdText);
    }
    catch(_com_error e)
    {
    m_pConnection->Close();
    m_pConnection=NULL;
    pNetFunctionCaller->NetShareDel(str6.GetBuffer(0));
    AfxMessageBox(e.Description());
    return 0;
    }
    //    szPath2
    try
    {
    vSQL="backup   database   relacart   to   disk='\\\\"+localip+"\\"+str6+"\\"+dlg.GetFileName()+"' WITH init";     
    m_pConnection-> Execute(vSQL,NULL,adCmdText);
    }
    catch(_com_error e)
    {
    m_pConnection->Close();
    //    m_pConnection->Release();
    m_pConnection=NULL;
    pNetFunctionCaller->NetShareDel(str6.GetBuffer(0));
//    vSQL="xp_cmdshell 'net use z: /delete'";
//    m_pConnection-> Execute(vSQL,NULL,adCmdText);
    AfxMessageBox(e.Description());
    return 0;
    }
    if( !pNetFunctionCaller->NetShareDel(str6.GetBuffer(0)) )
    {
    AfxMessageBox("Failed!");
    delete pNetFunctionCaller;
    return 0;
    }
    delete pNetFunctionCaller;

麻烦帮我看看上面代码，现在我要实现的是局域网内sqlserver数据库的远程备份还原。
我现在用安装系统的的用户名Administrator，密码为空就可以实现，但修改用户名或者密码就不能实现，请高手请教。