Solving system01.dbf block corruption without backups

Since this file is the Data Dictionary, you have lost your database. There is no substitute for a good backup and recovery strategy. In many cases, you can reinstall the operating system. You can even reconfigure it. You can also reinstall your application software. One can also reinstall Oracle and re-create the database. But in most every case, it is either impossible or very very difficult to re-create your data. This is why backups of your databases are vitally important. And backups are of no use if no one knows how to recover from them. So a sound, comprehensive backup and recovery plan is highly recommended.