急SQLDMO备份出现。[Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server 不存在或访问被拒绝,该怎么解决

protected void bfbtn_Click(object sender, ImageClickEventArgs e)        {            SQLDMO.Backup oBackup = new SQLDMO.BackupClass();            SQLDMO.SQLServer oSQLServer = new SQLDMO.SQLServerClass();            try            {                string filename = DateTime.Now.ToString() + ".bak";                oSQLServer.LoginSecure = false;                oSQLServer.Connect("local", "sa", "daili");                oBackup.Action = SQLDMO.SQLDMO_BACKUP_TYPE.SQLDMOBackup_Database;                oBackup.Database = "medicine";                oBackup.Files = @"E:\88789\医学\" + filename;                oBackup.BackupSetName = "medicine";                oBackup.BackupSetDescription = "数据库备份";                oBackup.Initialize = true;                oBackup.SQLBackup(oSQLServer);                if (dataBaseDB.AddDataBase(filename))                {                    Response.Write(dataBaseDB.clew("数据库备份成功！", "/admin/database/databaseList.aspx"));                }                else                {                    Response.Write(dataBaseDB.clew("数据库备份失败！", "/admin/database/databaseList.aspx"));                }            }            catch (Exception ex)            {                throw ex;            }            finally            {                oSQLServer.DisConnect();            }        }