ORA-19913: unable to decrypt backup
Cause: A backup piece could not be decrypted. This message is accompanied with another message that indicates the name of the encrypted backup that could not be restored. The reason could be either that an invalid password was entered, or that, when using transparent decryption, the database external security device is not open
Action: If password-based restore was enabled for this backup, then supply the correct password using the RMAN SET DECRYPTION command. If transparent restore was enabled for this backup, then ensure that the database external security device is open
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