oracle error- ORA-00308: cannot open archived log 'string'

ORA-00308:	cannot open archived log 'string'
Cause:	The system cannot access a required archived redo log file.
Action:	Check that the off line log exists, the storage device is online, and the archived file is in the correct location. Then attempt to continue recovery or restart the recovery session.

oracle error- ORA-00307: requested INSTANCE_NUMBER out of range, maximum is string

ORA-00307:	requested INSTANCE_NUMBER out of range, maximum is string
Cause:	The initialization parameter INSTANCE_NUMBER specified a number that was out of range.
Action:	Change INSTANCE_NUMBER to a valid range and restart the instance. The minimum value is one and the maximum value is the lower of the operating system-specific maximum or the MAXINSTANCES option specified in the CREATE DATABASE statement. See also your operating system-specific Oracle documentation.

ORA-00306:	limit of string instances in this database
Cause:	Starting this instance would exceed the maximum number of instances allowed for this database. This message occurs only with STARTUP shared and multiple instances.
Action:	You cannot start more than the lower of a) port-specific limit as to the number of instances b) the number of instances specified at create-database time