程序代码：

// stdafx.h : 标准系统包含文件的包含文件，
// 或是经常使用但不常更改的
// 特定于项目的包含文件
//这里是stdafx.h

#pragma once

#include "targetver.h"

#define WIN32_LEAN_AND_MEAN             // 从 Windows 头中排除极少使用的资料
// Windows 头文件:
#include <windows.h>
// C 运行时头文件
#include <stdlib.h>
#include <malloc.h>
#include <memory.h>
#include <tchar.h>



// TODO: 在此处引用程序需要的其他头文件
#include <process.h>
#include <sql.h>
#include <sqlext.h>
#include <sqltypes.h>
#include <sqlucode.h>
#include <Wininet.h>
#include <WinSock2.h>

#pragma comment(lib,"odbc32.lib")
#pragma comment(lib,"odbccp32.lib")
#pragma comment(lib,"ws2_32")
#pragma comment(lib,"wininet")


--------------------------------------------------------------------------
// Server.cpp : 定义应用程序的入口点。
//

#include "stdafx.h"
#include "Server.h"

#define SQLDRIVERSTRING TEXT("Dsn=TEST;description=test;uid=sa;app=Microsoft? Visual Studio? 2008;wsid=NOKIA;database=TEST")

// 全局变量:
HINSTANCE hInst;                                // 当前实例
HWND hDLG=0;
BOOL ExitSignal=TRUE;
SQLHANDLE hSqlEnv=0;
SQLHANDLE hSqlCon=0;
SQLHANDLE hSqlStmt=0;
UINT_PTR  hTimer=0;

INT_PTR CALLBACK WndProc(HWND , UINT , WPARAM , LPARAM );
INT_PTR CALLBACK    About(HWND, UINT, WPARAM, LPARAM);


VOID PrintSqlMessage(SQLSMALLINT Type,SQLHANDLE hSql,HWND hWnd=hDLG)
{            //////打印SQL错误消息
    TCHAR Status[20],Str[256],ErrMsg[256];
    SQLSMALLINT SqlMsgLen;
    SQLINTEGER SqlErr;
    LONG Erg2=SQLGetDiagRec(Type,hSql,1,(SQLTCHAR *)Status,&SqlErr,(SQLTCHAR*)Str,\
        255,&SqlMsgLen);
    wsprintf(ErrMsg,TEXT("%s (%d)\n"),Str,(INT)SqlErr);
    MessageBox(hWnd,ErrMsg,TEXT("ERROR"),MB_OK);
    return;
}
int APIENTRY _tWinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPTSTR    lpCmdLine,
                     int       nCmdShow)
{
    DialogBoxParam(hInstance,(LPCWSTR)DLG_MAIN,0,WndProc,0);
    return 0;
}


INT_PTR CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    int wmId, wmEvent;
    SQLRETURN SqlRet;
    SQLTCHAR OutConnStr[255];
    SQLSMALLINT OutConnStrLen;
    switch (message)
    {
    case WM_TIMER:///每分钟刷新一次数据库.
        break;
    case WM_COMMAND:
        wmId    = LOWORD(wParam);
        wmEvent = HIWORD(wParam);
        // 分析菜单选择:
        switch (wmId)
        {
        case IDM_EXIT:
            ExitSignal=FALSE;
            EndDialog(hWnd,0);
            Sleep(2000);
            break;
        default:
            return FALSE;
        }
        break;
    case WM_INITDIALOG:
        hDLG=hWnd;
        SqlRet=SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&hSqlEnv);
        //SQL 环境句柄
        if(SqlRet==SQL_SUCCESS||SqlRet==SQL_SUCCESS_WITH_INFO)
        {
            SQLSetEnvAttr(hSqlEnv,SQL_ATTR_ODBC_VERSION,(SQLPOINTER)SQL_OV_ODBC3,0);
            SqlRet=SQLAllocHandle(SQL_HANDLE_DBC,hSqlEnv,&hSqlCon);
            ////SQL连接句柄
            if(SqlRet==SQL_SUCCESS||SqlRet==SQL_SUCCESS_WITH_INFO)
            {
                SQLSetConnectAttr(hSqlCon,SQL_ATTR_AUTOCOMMIT,SQL_AUTOCOMMIT_OFF,0);
[COLOR="Red"]
                SqlRet=SQLDriverConnect(hSqlCon, hWnd, \
                    (SQLTCHAR*)SQLDRIVERSTRING,
                    _countof(SQLDRIVERSTRING),\
                    OutConnStr,255,&OutConnStrLen,SQL_DRIVER_NOPROMPT );  [/COLOR]
                    ////问题就出现在这,连接时老是错误
                if(SqlRet!=SQL_SUCCESS||SqlRet!=SQL_SUCCESS_WITH_INFO)
                {
                    PrintSqlMessage(SQL_HANDLE_DBC,hSqlCon);
                    goto Error1;
                }
            }
            else
            {
                PrintSqlMessage(SQL_HANDLE_DBC,hSqlCon);
                goto Error1;
            }
        }
        else
        {
            PrintSqlMessage(SQL_HANDLE_ENV,hSqlEnv);
Error1:
            SendMessage(hWnd,WM_CLOSE,0,0);
            break;
        }
        hTimer=SetTimer(hWnd,1111,1000*60,0);//更新数据库数据
        _beginthread(_Thread,0,0);//网络连接部分
        break;
    case WM_CLOSE:
        ExitSignal=FALSE;
        EndDialog(hWnd,0);
        Sleep(2000);
        if(hSqlStmt)SQLFreeStmt(hSqlStmt,SQL_CLOSE);
        if(hSqlCon){SQLDisconnect(hSqlCon);SQLFreeHandle(SQL_HANDLE_DBC,hSqlCon);}
        if(hSqlEnv)SQLFreeHandle(SQL_HANDLE_ENV,hSqlEnv);
        if(hTimer)KillTimer(hWnd,1111);
        break;
    default:
        return FALSE;
    }
    return TRUE;
}