imp orcale导入数据库命令急该怎么解决

imp orcale导入数据库命令急啊
安装oracle时我把标识和数据库名不一致请看我在select * from v$instance;查询到的
INSTANCE_NUMBER INSTANCE_NAME HOST_NAME  
  1 yan0526 YAN  
再把情况说下我用以下命令:
imp system/sys@yan0526 FILE=E:\yan68.dmp FROMUSER=(Sb_Js,) TOUSER=(Sb_Js) log=imp_log.txt
跟踪的提示：
IMP-00058: 遇到 ORACLE 错误 12154
ORA-12154: TNS: 无法解析指定的连接标识符
IMP-00000: 未成功终止导入

我贴下 LISTENER.ora
SID_LIST_LISTENER =
  (SID_LIST =
  (SID_DESC =
  (SID_NAME = PLSExtProc)
  (ORACLE_HOME = F:\oracle\product\10.2.0\db_2)
  (PROGRAM = extproc)
  )
  (SID_DESC =
  (GLOBAL_DBNAME = yan)
  (SID_NAME = yan0526)
  )
  )

LISTENER =
  (DESCRIPTION =
  (ADDRESS = (PROTOCOL = TCP)(HOST = yaN)(PORT = 1521))
  )

我贴下 LISTENER.ora

YAN =
  (DESCRIPTION =
  (ADDRESS_LIST =
  (ADDRESS = (PROTOCOL = TCP)(HOST = yaN)(PORT = 1521))
  )
  (CONNECT_DATA =
  (SERVER = DEDICATED)
  (SERVICE_NAME = yan)
  )
  )

EXTPROC_CONNECTION_DATA =
  (DESCRIPTION =
  (ADDRESS_LIST =
  (ADDRESS = (PROTOCOL = IPC)(Key = EXTPROC0))
  )
  (CONNECT_DATA =
  (SID = PLSExtProc)
  (PRESENTATION = RO)
  )
  )

我贴下sqlnet.ora

SQLNET.AUTHENTICATION_SERVICES= (NTS)

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)
现在本人真是不知道咋办了唉，跪求答案哇。谢谢尼



------解决方案--------------------

你是在本机执行的imp指令吗？
tnsping yan0526 能否响应？
一般这种情况下，我的做法是， 借助oracle的net config assistant 把监听和 tns连接重新配置一遍再试试。 
检查一下 你的tnsname.ora的yan0526 说明前面是否有空格。