Accidentally Installed Windows Over OS X

Discussion in 'Windows, Linux & Others on the Mac' started by Leng, Jul 13, 2009.

  1. Leng macrumors newbie

    Jul 13, 2009
    I see the other thread on here, but it didn't help me.

    Okay, so I have a black Intel-based Macbook that had OS X on it. I booted with Windows XP install disc and installed Windows over the entire HD.

    Everything worked fine, windows ran, but I didn't realize how foolish it is to erase OS X until it was too late.

    I'm trying to install the Mac OS again. When I try to boot from "Mac OS X Install Disc 1" - either by holding down 'c' during startup or holding down option and clicking on the DVD - it brings up a gray screen with the Apple logo and then restarts the computer after a few seconds. It is the DVD that came with my macbook.

    The computer will boot to the Windows XP cd - I used it to remove the NTFS partition with windows and create a new partition and formatted it as FAT. The same thing happens when I try to boot from the OS X DVD.

    I've tried to boot Knoppix in order to format the partition to hfs or hfs+ but I can't get Knoppix CD to boot either.

    I've tried every combination of "holding down keys during booting" with an unpartitioned drive, with a 20GB FAT partition, with a 20GB FAT32 partition, etc. I've tried everything I can think of or find on this forum or on any other forum.

    Any help would be greatly appreciated - thanks so much!

    By the way, I have another Macbook but no firewire cable. I've checked the OS X install DVD on other macbooks and it's totally mint, perfect working order. It's totally blowing my mind how this new apple macbook is booting off the Windows XP install disc but not off its OWN install disc.
  2. killerrobot macrumors 68020


    Jun 7, 2007
    Can you boot into safe mode (holding down shift)?

    Not sure if that's really do anything since you can't boot off the disk but it might be worth a try.
  3. Leng thread starter macrumors newbie

    Jul 13, 2009
    Holding either shift or both shift keys has no effect. The only "holding down any possible number of key combinations while booting up" that makes any discernible change is when I put in the OS X install disc 1 and boot while holding 'c' down. Then I can see an apple logo - just a glimpse of apple on an otherwise empty machine - just the logo, not the circle loading thing, and then the computer restarts. If I hold 'c' again after it restarts, it does the same thing.
  4. MacDawg macrumors Core


    Mar 20, 2004
    "Between the Hedges"
    You should be able to boot from the CD by either holding "C" or "Option"
    Since you say that is not the case, it is possible your DVD is messed up

    I would suggest trying your DVD on another Mac to test it
    Or better, trying another DVD (retail Leopard) on your Mac

    Booting from the DVD will allow you to erase the disk from Disk Utility and choose Mac OS Extended (Journaled) and reinstall Leopard

    I hope you had a backup of your data :eek:

    Edit: You edited your original post. The DVD from your other Mac may not work unless they are the exact same model. I would try to find a retail copy of Leopard to try it. If you can boot the other Mac and can locate a Firewire cable, then you should be able to boot into Target Disk mode and erase/format the disk that way.

    Woof, Woof - Dawg [​IMG]
  5. Leng thread starter macrumors newbie

    Jul 13, 2009
    I've tested the DVD on other macbooks, it works just fine. I've also used the install disc from other macbooks on this macbook, and the same thing happens. I've used every possible combination of holding keys down while starting the machine to no avail - the only thing that makes any discernible change whatsoever is when I start the macbook with OS X install disc 1 in it and hold 'c' down as it starts up. Then it shows me an apple logo - just a glimpse of apple on an otherwise no-OS machine - for a few seconds before restarting.

    No data was lost, it's a clean, new machine that was running OS X just fine, and then Windows just fine, but now I want OS X back and can't get it.
  6. killerrobot macrumors 68020


    Jun 7, 2007
    Do you have access to another mac at the moment?

    See if you can boot into target disk mode.

    EDIT: I see MacDawg just said the same - missed the edit before.
  7. Leng thread starter macrumors newbie

    Jul 13, 2009
    I have another Mac but no firewire cable and no access to firewire cables.
  8. killerrobot macrumors 68020


    Jun 7, 2007
  9. Leng thread starter macrumors newbie

    Jul 13, 2009
    I can only do that after installing OS X on it.

    I've been told that if I take it into the mac store they'll charge me for a new HDD. My HDD is working fine, I can install Windows just fine, make FAT / NTFS partitions, etc. I just can't boot to the OS X disc with the provided, perfectly fine DVD or with any other OS X install discs to use disk utility to fix said HDD.
  10. killerrobot macrumors 68020


    Jun 7, 2007
    Yeah I know. That's why I said BUT...

    Just letting you know I'm still with you and trying to think of something.

    I'd still give it a go though, make sure the latest is installed on the running mac, plug in the ethernet, and restart the other holding down t.
  11. Leng thread starter macrumors newbie

    Jul 13, 2009
    Oh, I'm sorry. I'm just stressing out over this. :(

    I did give it a go, to no avail.

    Thanks for the good ideas so far...
  12. killerrobot macrumors 68020


    Jun 7, 2007
    No worries, I'd be stressing too.

    During the windows startup does it give you the option to press f8, and go Windows Advanced Boot Options Menu?

    Does it give you and option to boot off the FAT32 partition you created earlier or set cd/dvd a first boot option?

    Select one of those and try booting of the OSX install disk.

    If that doesn't work then it seems as though you might have to use the windows startup disk, boot off it, wipe the partitions and reformat everything with fat32.

    Then try booting off the OSX install disk again after that.:(

    I know its not what you wanted to hear, but I'd have to think that the NTFS has made the HD non-writeable. Whatever that has to do with not allowing it to boot from the OSX install disk I'll never know.

    EDIT: Best of luck. I'm not familiar with Knoppix. Sorry about the wait time with the reformatting. :(
  13. Leng thread starter macrumors newbie

    Jul 13, 2009
    Hmm - didn't see that option, but I'm going ahead and using the Windows CD recovery console. I already partitioned the whole HD to one partition and am now formatting that partition (err, the entire HD) to Fat32 like you said.

    Will take a couple hours.... but worth a try. Thanks again, Killerrobot. I appreciate your brainstorming!!

    If anyone else knows anything that might format it to a better filesystem or anything - I'm all ears. Knoppix didn't run, but maybe some other Linux live CD would?
  14. redking31591 macrumors 6502

    Jul 10, 2008
    try a gparted live cd. it runs on a mac I have used it before
  15. milk242 macrumors 6502a

    Jun 28, 2007
    Try this:

    Boot up with your os x disk.

    Go to disk utility

    Select the hard-drive, not the partition. For example my partition is named Macintosh HD and my hard-drive is named 250.06GB Hitatchi...

    Select the partition tab

    Under the current scheme, select partition 1 then click on the options button and change the partition table to guid.

    Select Mac OS Extended journaled in the format drop-down.

    Click apply

    Hope that fixes your problem
    *Note: this will delete your windows partition.
  16. Leng thread starter macrumors newbie

    Jul 13, 2009
    All I'm trying to do is boot from the OS X DVD.

    If I could do that, I'd be happy.

    I made a gparted live CD and will try that if formatting the whole HD to Fat32 doesn't help.

    EDIT: After reformatting the whole drive to Fat32, the OS X install disk still wouldn't boot.

    I used GParted to reformat the whole hard drive to HFS+, still no dice.

    *Pulls hair out*
  17. vertigo78 macrumors regular

    Oct 2, 2008
    get an enclosure to put your hd in, connect it to your macbook, reformat, put the hd back, and try the install disc again. if it still doesnt work, put it back in the enclosure and try using carbon copy cloner to make a bootable copy of your working macbook hd.
  18. xlii macrumors 68000


    Sep 19, 2006
    Millis, Massachusetts
    I second what Vertigo has said. If you can't boot from the OSX disk by holding down the option key... and then formatting the drive... do the above... it is good advice and will solve your problem.

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