oracle error -- ORA-00305: log string of thread string inconsistent; belongs to another database

ORA-00305:	log string of thread string inconsistent; belongs to another database
Cause:	The database ID in the redo log file does not match the database ID in the control file. This redo log file is not from the current database.
Action:	Specify the correct redo log file, then retry the operation.

oracle error -- ORA-00304: requested INSTANCE_NUMBER is busy

ORA-00304:	requested INSTANCE_NUMBER is busy
Cause:	An instance tried to start by using a value of the initialization parameter INSTANCE_NUMBER that is already in use.
Action:	Either a) specify another INSTANCE_NUMBER, b) shut down the running instance with this number c) wait for instance recovery to complete on the instance with this number.

ORA-00303:	cannot process Parallel Redo
Cause:	A redo log containing Parallel Redo has been detected. The current Oracle release cannot process this format of redo.
Action:	Use a later release that supports Parallel Redo. to process this log.