Cause: The block size as stored in the control file header is
different from the value of the initialization parameter
DB_BLOCK_SIZE. This might be due to an incorrect setting of
DB_BLOCK_SIZE, or else might indicate that the control file has
either been corrupted or belongs to a different database.
Action: Restore a good copy of the control file. If the control file is
known to be clean set the DB_BLOCK_SIZE to match control file
headers block size value.