Oracle Error Message
ORA-19556: required destination LOG_ARCHIVE_DUPLEX_DEST currently is deferred
Reason for the Error
The destination for parameter LOG_ARCHIVE_DUPLEX_DEST was deferred when it was required to be enabled. The destination was deferred automatically when an ALTER SYSTEM command for parameter LOG_ARCHIVE_DEST defined a destination which duplicated an existing LOG_ARCHIVE_DUPLEX_DEST parameter destination.
Solution
Change the destination value for the LOG_ARCHIVE_DUPLEX_DEST parameter.