If I install OSX from an External HD, will it erase my External?

Discussion in 'Mac Basics and Help' started by simplex, Aug 31, 2011.

  1. simplex macrumors newbie

    Aug 31, 2011
    I'm installing Snow Leopard and need to know if once I boot up from my External HD and begin the OSX install process, will it erase the data from the External? Sorry if this has been answered or it's in the wrong section, I'm new here, cheers.
  2. Mal macrumors 603


    Jan 6, 2002
    Why in the world would it erase your external hard drive? I'm sorry, I just don't understand these types of questions.

    Simple answer: No, not unless you explicitly tell it to by launching the Disk Utility program and walking through the several steps and warnings to manually erase the drive. No OS X update (released to the public via DVD or download) has ever required you to erase your hard drive in order to install it, or done such an operation without the user seeking out and choosing that option within the installer's steps. In Snow Leopard, Apple made it more difficult, not less, to accidentally erase your hard drive by removing the option from the Installer.

  3. simplex thread starter macrumors newbie

    Aug 31, 2011
    Sorry to sound stupid, I just figured it's better to be too careful than do something dumb like erasing everything on accident. It's just that I heard in order to install OSX from an external, that you may need to partition the drive, and when I did this I was prompted that this would erase everything, so obviously I didn't apply. Can I still boot from the .dmg even without a partition? That's where my question stemmed from, wasn't sure if it would erase my external if I didn't partition it when I install Snow Leopard.

Share This Page