exp -00056 ora-12638 Credential retrieval failed

wengtf

11.2.0.2 on windows 2008 64bit
db 运行了好几年了，5月份一次exp 导出备份的时候。
C:\Users\sup_guj.LLOYDS>exp reserve/xxx file=E:\Data_Expdp_Prod\exp_reserve_prod_%date:~0,10%.dmp log=E:\Data_Expdp_Prod\exp_reserve_prod_%date:~0,10%_dmp.log owner=reserve

Export: Release 11.2.0.2.0 - Production on Tue May 14 09:47:04 2013

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EXP-00056: ORACLE error 12638 encountered
ORA-12638: Credential retrieval failed
EXP-00000: Export terminated unsuccessfully

用户重置过一次密码，该问题消失，最近突然同一账号又出现了该问题，参考过[ID 1225063.1]

wengtf

用户的数据库服务器存在域里面，刚咨询过microsoft，有域就会配置KERBEROS AUTHENTICATION.

Maclean Liu(刘相兵

配过 KERBEROS AUTHENTICATION吗？