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ORA-00391:

All threads must switch to new log format at the same time
Cause: An attempt to switch the current log of a single thread is not allowed because the compatiblity requirements force a new log format version number. When changing log formats, all threads must switch to the new format at the same time.
Action: Open the database to cause the coordinated log switch. If that is not possible then return to the same software version and compatibility setting last used to open the database.