The specified redo log file does not contain information that the PowerExchange Express CDC for Oracle log reader requires in the second block of the file header. The file might not be a log file, or it might be a corrupted log file. In an Oracle RAC environment, this message includes the name of the relevant RAC member.
The log reader tries to use the alternate log file that has the same sequence number. If this alternate log file does not exist, CDC processing ends.
Restore the log file, or if you cannot restore the log file, rematerialize the target. Then cold start the CDC session.