Restoring archive backups created with version 12   Archive backups created with version 12 database servers cannot be restored with version 11 or earlier database servers.

Free pages are eliminated in archive backups   By default, archive backups skip some free pages, which can result in smaller and potentially faster backups. Free page elimination has no affect on the back up of transaction log files because transaction log files do not contain free pages. So, databases with large transaction log files may not benefit as much from free page elimination as databases with small transaction log files. You can control this behavior using the BACKUP statement's FREE PAGE ELIMINATION clause or using the Backup Database Wizard. See BACKUP statement.

When you are restoring a strongly-encrypted database that was backed up with free page elimination on, the encryption key for the database must be specified. You can specify the encryption key using the RESTORE DATABASE statement's KEY clause or using the Restore Database Wizard.