13 Replies Latest reply: Jul 16, 2010 2:42 PM by R C-R
berrett Level 1 Level 1 (0 points)
I need to reformat my hard drive for various reasons. I can't find the original OSX disc that came with my computer, but I do have the Snow Leopard upgrade disc. Can I wipe the hard drive clean and reinstall using the SL Upgrade disc?

MacBookPro, Mac OS X (10.6.4)
  • Martin Pace Level 5 Level 5 (5,110 points)
    Yes, there is no requirement to prove you are upgrading from the previous system. It just works!
  • R C-R Level 6 Level 6 (14,920 points)
    That depends on what you mean by "upgrade disc." If it is a retail Snow Leopard disc, then yes you can -- it is a full function, stand alone installer.

    But there are other Snow Leopard discs that are just upgrade ones that require a previous version of the OS to be installed first, for instance the "CPU Drop-in DVD" that were 'dropped in' the boxes of some Macs that came with Leopard installed after Snow Leopard was released.

    Either way, note that Snow Leopard installer discs, unless they are grey ones that came with the computer, will not install the bundled software that came with that Mac, like iLife.
  • berrett Level 1 Level 1 (0 points)
    Wow - thanks for the warning. It's a purchased ($30, I think) version of the software, so from what you both have said I assume I'll be able to do the reformat with it. However, if I don't get iLife back then I definitely don't want to go down that road.

    Maybe I need to explore other options, but I'm out of ideas. Our computer locks up almost daily, requiring a hard reboot. It is slower than heck. Our kids have screwed it up pretty good.

    Maybe we need to turn the house inside out and find the original disc.

    Thanks for the info.
  • dbsneddon Level 4 Level 4 (1,525 points)
    Maybe if you describe the "various reasons" you think you need to reformat
    and reinstall you may find you don't really need to.

    Dave
  • Neville Mayfield Level 4 Level 4 (1,305 points)
    I presume you don't have a backup for your drive. Buy a big-enough external drive, download a program like SuperDuper and clone your drive to the external. This will save all your personal files as well as the iLife applications and any others you have.

    When you've done this you can then use the SL dvd to reformat & reinstall the OS. Then use Migration Assistant to copy back all your other files & apps.

    Neville
  • berrett Level 1 Level 1 (0 points)
    Doesn't it defeat the purpose to clone the drive though? I'm assuming we're getting the freezes and the slowness from corrupted files, viruses, or some other such thing. If I clone everything and reinstall it that way, I'll just have the same computer back again. Am I right, or am I misunderstanding something?

    Someone asked why I want to do this: My kids use this particular iMac. I don't know what they have done to it, but now it locks up (requiring a hard reboot) a few times a week. It's so slow that you click on applications then leave the room while you wait for them to load. We can't figure out what the problem is, so I just wanted to start over.
  • Allan Eckert Level 8 Level 8 (46,030 points)
    Hi berrett.rice;

    First of all if you set up accounts without admin privileges for your kids then they will only be able to screwup their own account and not the whole Mac.

    Next is forget about virus. They don't exist on Mac at the present time.

    If you clone your system to another formated drive, the directory structure on that drive would not be corrupt so when you clone if corruption of the directory is causing the problem, the clone should not have that problem. If it were my Mac I would create the clone and boot from it. See if you have the problem with the clone. If you don't have the problem with the clone, then cloning back again after reformatting the internal drive should fix the problem.

    ___________________

    Allan
    tiger
  • berrett Level 1 Level 1 (0 points)
    Allan - Thank you. I will set up accounts next time for sure.

    As a follow up: I'm I correct that you're saying it is likely the directory structure that is corrupt and not something in the operating system itself? If this is the case, couldn't I just create a new account, move everything over and get it working properly, then delete the other accounts? Wouldn't that be the same as reformatting -- if it's a directory structure problem and not an installation problem?
  • R C-R Level 6 Level 6 (14,920 points)
    Allan Eckert wrote:
    If you clone your system to another formated drive, the directory structure on that drive would not be corrupt so when you clone if corruption of the directory is causing the problem, the clone should not have that problem.


    This is not necessarily true: a clone made by the +block copy+ method will preserve any directory corruption on the original, since it is just a block-by-block copy without regard for what those blocks contain. Several cloning utilities, including Disk Utility & Carbon Copy Cloner, will use block copying when possible because it is faster than the file copy method. The file copy method (the only one used by SuperDuper!) is not a workaround for this -- it will eventually fail if it can't resolve the bad links in the corrupted directory structures, the same as would a Finder copy (which is essentially what it is).

    However, running Disk Utility's verify or repair disk step beforehand will generally at least detect if not repair the directory damage. So whatever cloning method you use, run this before making the clone. Most dedicated cloning applications, including Carbon Copy Cloner & SuperDuper!, have built-in options to run the verify disk step automatically, so use them.

    IOW, cloning doesn't repair file or directory damage. A good cloner "blesses" the system & performs the other necessary chores to make the clone bootable that copying alone cannot do, & may do other things like skip copying temporary files that will just be created anew on each startup anyway, but these are not repair steps.
  • Allan Eckert Level 8 Level 8 (46,030 points)
    Hi berrett.rice;

    The directory structure is much lower then a new user account. It is that basic foundation of the disk with the operating system on top of that and then user accounts on top of that.

    The directory structure can be test with Disk Utility by doing a Verify. Personally I prefer to boot from the install DVD and repair it from there using Disk Utility.


    ___________________

    Allan
    tiger
  • berrett Level 1 Level 1 (0 points)
    Thanks to everyone for your patience and advice.

    I booted from the Snow Leopard upgrade disc. I ran Disc Utility and verified and repaired permissions. I also verified and repaired the disc.

    The only odd thing was a message that I got after the Permissions verify/repair. It said: Warning SUID File System/library/coreservices/remotemanagement/ARDAgent.app/contents/MACOS/ARDAge nt" has been modified and will not be repaired.

    Should I be concerned about that message?

    Other than that it seemed to go along just fine.
  • Chris CA Level 9 Level 9 (77,225 points)
    I can't find the original OSX disc that came with my computer

    ...
    However, if I don't get iLife back then I definitely don't want to go down that road.

    You can contact Apple and for a nominal fee (~$40) get a set of original DVDs that came with your computer.
  • R C-R Level 6 Level 6 (14,920 points)
    Should I be concerned about that message?


    No.