因单位需要新购置了一台HP 服务器来采集多个数据库的数据，安装了WIN 2008 R2 64位系统，安装ORACLE客户端后拷贝已有的tnsnames.ora文件，发现tnsnames.ora中某个连接报ORA-12537: TNS: 连接关闭。而其余几个都可以正常连接。但这个连接失败的服务器在其他电脑（win2003 32位+32位oracle 9i客户端）上却可以正常的连接上。我在这个新机器上先后安装了win32_11gR2_client、win64_11gR2_client都是报同样的错误。下面是几个相关的配置文件
1、tnsnames.ora文件
# tnsnames.ora Network Configuration File: D:\app\Administrator\product\11.2.0\client_1\NETWORK\ADMIN\tnsnames.ora

# Generated by Oracle configuration tools.

WG =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.1.8)(PORT = 1521))
)
(CONNECT_DATA =
(SERVICE_NAME = infodb)
)
)

WG2 =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.2.6)(PORT = 11521))
)
(CONNECT_DATA =
(SERVICE_NAME = nb.infodb)
)
)

# WG是可以正常连接的，WG2却报ORA-12537: TNS: 连接关闭

2、sqlnet.ora文件
# sqlnet.ora Network Configuration File: D:\app\Administrator\product\11.2.0\client_1\network\admin\sqlnet.ora
# Generated by Oracle configuration tools.

# This file is actually generated by netca. But if customers choose to
# install "Software Only", this file wont exist and without the native
# authentication, they will not be able to connect to the database on NT.

SQLNET.AUTHENTICATION_SERVICES= (NTS)

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)

2008的防火墙也关闭了，还是没有解决。
这个问题已经困扰了我好多天，急切盼望高人指点迷津。拜谢了。。。