İnternet Recovery ile sıfırdan Mavericks yüklemesi yapabilirsiniz. Bilgisayarınızı açma tuşuna bastıktan sonra Command ve R tuşlarına birlikte basılı tutun. Recovery ekranı gelince bir internet bağlantısı yaparak diskinize OsX'i yeniden kurabilirsiniz. Detaylı bilgi için şuraya bakabilirsiniz . http://www.apple.com/osx/recovery/
Eğer Time Machine yedeğiniz var ise ; Command + R tuşlarına bastığınızda seçenekler arasında bulunan "Time Machine yedeğinden geri yükle" seçeneğinde sıfırdan kurulum yapmadan halledebilirsiniz.
Restoring your entire system from a backup
If you are restoring a backup made by a Mac to the same Mac
Hold down the Command and R keys at startup to start the computer from the Recovery system. The Recovery menu that appears includes the option to restore from a Time Machine backup. If you are using Mac OS X Snow Leopard, start your computer from the installation disc. Then use the "Restore From Time Machine Backup" utility.
Note: If "You can't restore this backup because it was created by a different model of Mac" appears when restoring a backup that was made on a different Mac, follow the onscreen instructions. If you are trying to restore your backup from one Mac to another Mac, use Migration Assistant to transfer data from the backup instead, as described in the next section.
http://support.apple.com/kb/ht1427