Accidentally Deleted My Mac OS

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MathcoreRomeo


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I put my Leopard 1 disc in the drive, I restarted my Mac, and now it tells me, "No bootable device -- insert boot disk and press any key." I pressed any key, and it won't do anything.

How do I reinstall my Mac OS?
 
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Your Mac partition is likely still there. Hold down the option key when you reboot, and select it from the menu.
 
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Did this by chance happen after you attempted to install Windows via Boot Camp?
 
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Yes, this happened after I tried to install Windows. There was only one partition to choose from, and I figured it was the one Boot Camp made...

I tried holding option down, I just get a blank screen.

Edit: I got the option to reinstall Mac from my disc after holding down option. Is my other OS definitely gone, though?
Edit 2: It asks me where I want to install my Mac OS, but there is nowhere to choose from. The window is blank.
 
vansmith

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If you only had one partition on your machine and you installed Windows on it, then you only have Windows installed. When you went to install Windows, what was that partition labeled as? Did you follow the BC installation guide? Did you use the Boot Camp Assistant (/Applications/Utilities/Boot Camp Assistant.app)?

EDIT: If you are trying to reinstall OS X and the disk doesn't show up, run Disk Utility from the install disc and format the drive first.

Did you have a backup of all your data before this happened?
 
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vansmith said:
If you only had one partition on your machine and you installed Windows on it, then you only have Windows installed. When you went to install Windows, what was that partition labeled as? Did you follow the BC installation guide? Did you use the Boot Camp Assistant (/Applications/Utilities/Boot Camp Assistant.app)?

EDIT: If you are trying to reinstall OS X and the disk doesn't show up, run Disk Utility from the install disc and format the drive first.

Did you have a backup of all your data before this happened?
Click to expand...

I didn't back anything up because I didn't expect this to happen. The partition was labeled as 'unkown', I think. I followed the guide, but when I went to install Windows, it just kept going back to the set up and never did anything.

Also, which disk am I supposed to click on the Disk Utility? I have the Leopard Install disk, and some other 'Disk 0' think. Also, how to format the drive from Disk Utility?
 
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MathcoreRomeo said:
Yes, this happened after I tried to install Windows. There was only one partition to choose from, and I figured it was the one Boot Camp made...

I tried holding option down, I just get a blank screen.

Edit: I got the option to reinstall Mac from my disc after holding down option. Is my other OS definitely gone, though?
Edit 2: It asks me where I want to install my Mac OS, but there is nowhere to choose from. The window is blank.
Click to expand...

You're going to have to erase the disk, format, and then reinstall OS X. You may have accidently overwrote your OS X partition and now it's gone.

Boot with your install media (Leopard DVD 1) but instead of entering the OS X installation process, escape out of it and select Utilities from main menu. Then select Disk Utilities. Check to see if there are two partitions showing or just one. If a second partition shows up, erase it and drag the line so that the entire drive is one partition.

1. Select the entire drive from the right side and then choose erase at the top of the screen.

2. Now select the format: MacOS Extended for Mac use only.

3. Name the drive MacIntosh HD

4. Click on erase at the bottom of the screen, then click erase again on the second window. Should take a few minutes before it's done.

5. Now you can proceed to install OS X and all your applications. Be sure to run update after installation is finished.

Note: If you made a Time Machine backup before all this happened, you can skip step 5 and restore instead of having to install OS X and all apps again.

Regards.
 
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chscag said:
You're going to have to erase the disk, format, and then reinstall OS X. You may have accidently overwrote your OS X partition and now it's gone.

Boot with your install media (Leopard DVD 1) but instead of entering the OS X installation process, escape out of it and select Utilities from main menu. Then select Disk Utilities. Check to see if there are two partitions showing or just one. If a second partition shows up, erase it and drag the line so that the entire drive is one partition.

1. Select the entire drive from the right side and then choose erase at the top of the screen.

2. Now select the format: MacOS Extended for Mac use only.

3. Name the drive MacIntosh HD

4. Click on erase at the bottom of the screen, then click erase again on the second window. Should take a few minutes before it's done.

5. Now you can proceed to install OS X and all your applications. Be sure to run update after installation is finished.

Note: If you made a Time Machine backup before all this happened, you can skip step 5 and restore instead of having to install OS X and all apps again.

Regards.
Click to expand...

I clicked on the Windows Disk, Partition, thing (Or whatever part of it I have on my system) and went to erase, but it doesn't let me click anything at all.
 
dtravis7

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In Disk Utility point at the first listing on the left for the hard drive. Go to the Partition Tab and click on and set it to 1 partition. Then under Options select GUID Partition table. Click on Apply. Let us know if that works.
 
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dtravis7 said:
In Disk Utility point at the first listing on the left for the hard drive. Go to the Partition Tab and click on and set it to 1 partition. Then under Options select GUID Partition table. Click on Apply. Let us know if that works.
Click to expand...

I can't click on anything in there either. All of the buttons are grey'd out and such.
 
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Thanks, that link helped. Now, I erased/renamed that Windows HD, I guess. What was once called 'disk0' is now called 'Macintosh HD'. Macintosh HD is a subcategory for something called 'FUJITSU MHY2250BH Media. Is that what it's supposed to be?

Edit: Still can't select anything to install my Mac OS to.
 
cwa107

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Yes. What you're seeing as the top level is the model of your hard drive.
 
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Nevermind that edit. I got it to download.

Just a random question- Why is it that my HD is supposed to be 250GB, but it is only 232GB when it has nothing on it?

Also, thank you all very much for your time and helping me get this to work.
 

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