ORA-39188: unable to encrypt dump file set
Cause: Data Pump could not create an encrypted dump file set. This message will be accompanied by other messages that give more details about why the encrypted dump file set could not be created. The most common reason for this message is that you are trying to create a dump file set that can be transparently decrypted, and the database external security device is not open.
Action: If the external security device is not open, then open it. If the external security device is not configured, then the only type of encrypted dump file set that you can create is a password-based dump file set.
ORA-39188: 不能加密dump档案集
详细说明：
ORA-39188是Oracle数据库的一个通用错误。当用户尝试在数据库和文件系统之间使用加密时，将引发此错误。
ORA-39188发生时，Oracle提供以下原因：“指定的文件已被加密，无法加密另一个文件。”
此错误通常会发生在以下情况下：
1.用户试图在同一流中多次导出时，将第二个导出尝试加密；
2.当用户试图使用同一加密密钥重新加密相关文件集时；
3.当用户试图为单个导出使用多个加密密钥时。
处理ORA-39188错误的正常方法是确保相关文件只被加密一次。当此次试图无法实现时，应更改加密密钥，并确保对对应导出和/或导出流不使用加密参数。