How do I reinstall OS Lion without a DVD

There's only a few ways to do it.
All of them require you to perform a backup of you're personal documents!

1. Restart you're MAC and press the "ALT" key, until the screen shows two drives. One represents your hard drive (with the OS installed and you're personal documents), the other represents the repair disk utility (that allows you to erase or re-install the OS). Select the "Repair Disk Partition". Then re-install Lion. (This partition works the same way a OS Install DVD would work).

2. You could buy the Lion OS Thumb USB Drive, from the Apple Store. Connect the USB to a USB port, then boot you're MAC from it (once agin, press "ALT", and then select the USB drive on the screen). It works just like a OS Install DVD.

Once you have it remember once this: choosing the second option will have a small difference! When you install the Lion OS using the Thumb USB Drive, you won't create a "Repair Disk Partition". this means that every time you decide to erase you're HD, you'll need the USB Drive you bought!

• Answered by José C from Rio Tinto
• 11/09/2011