ORA-12170 TNS:Connection timeout occurred 错误, 知道的进来解解

用pl/sqldev 工具登录,报如下错: 
     ORA-12170 TNS:Connection timeout occurred
tnsnames.ora里面配置的:      HOME_IDSGD =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = LENOVO-3AA34578)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = idsgd)
    )
  )防火墙, 杀毒软件都关了的.
请大家都来PP