So I have a 2009 iMac 24" 2.66GHz 4+640GB that I accidentally deleted macOS on. I thought it would be fun to do a bootcamp installation of Windows XP, so I partitioned 80GB of storage for it. when I entered the setup, there was only 1 place I could install on and it was 131000MB, so 131GB and I only gave it 80 gigs. so I thought, "I should just install anyways maybe the partitioning software game it a bit more room to install windows on". No. it did not. when setup had completed I wanted to boot back into macOS 10.5.8 because I did what I wanted to do, but when I held down the option key only windows was available to boot into. I don't have any macOS installation discs either so I have no way of reinstalling it so what do you recommend I do? I seriously have no idea how to fix this
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Help I accidentally deleted macOS from my iMac!
- Thread starter TheMasterOfTech
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plug in an Ethernet cable--- boot while holding Option. wait a little while when on the boot loader screen. You'll eventually see Internet Recovery. Or you can try without an Ethernet cable and just hop onto your Wi-fi network(also available via the boot loader / startup disk screen when holding Option on boot)
Internet recovery is the way forward as it will fetch the last know available macOS for your iMac and you can install again.
There's also Internet Recovery hotkeys to press while cold booting. Turn off your iMac.. hold down Option+Command+R on boot. I believe there's an even deeper Interne Recovery that will fetch the original Mac operating system that came with your Mac back in the day.
That hotkey is, I think. Command+Option+Shift+R on a cold boot. I am certain that if you are already on the boot selector screen(the black one) that you can use all these hotkeys here too without having to cold boot you iMac.
Btw.. the waiting for the Internet Recovery logo to come up by itself might be 10 seconds and it might be a 30 seconds. If you have a minute to spare, then I say press all the keys you can on boot and also wait it out for a bit.
Internet recovery is the way forward as it will fetch the last know available macOS for your iMac and you can install again.
There's also Internet Recovery hotkeys to press while cold booting. Turn off your iMac.. hold down Option+Command+R on boot. I believe there's an even deeper Interne Recovery that will fetch the original Mac operating system that came with your Mac back in the day.
That hotkey is, I think. Command+Option+Shift+R on a cold boot. I am certain that if you are already on the boot selector screen(the black one) that you can use all these hotkeys here too without having to cold boot you iMac.
Btw.. the waiting for the Internet Recovery logo to come up by itself might be 10 seconds and it might be a 30 seconds. If you have a minute to spare, then I say press all the keys you can on boot and also wait it out for a bit.
Unfortunately a 2009 iMac doesn't support Internet Recovery so getting macOS reinstalled will be a bit more complicated.
If the OP has another Mac available then they can download an OS installer on that.
Oh snap... I am terrible at this. I'll hand over the help to those better than me. Thanks for correcting me
It still only shows to boot into windows because since it's a early 2009 it doesn't support it
Yikes, well you have a MacBook Pro that you can use - if I'm reading your signature correctly. Use that to find the latest macOS that your iMac supports and try that?
With finding, I mean downloading from Apple. Apple has files on the ready for quite a few.
support.apple.com
With finding, I mean downloading from Apple. Apple has files on the ready for quite a few.
How to download and install macOS – Apple Support (UK)
Download and install current or previous versions of the Mac operating system on compatible Mac computers.
yes I do have one that works, but it doesn't have a cd drive built in and I don't have a external one that I can plug in. I don't have any other Macs, or any other computers that work for that matter, that have a cd drive so I literally have to idea what to do now.
I'm certain that your iMac can boot off a USB key?! try getting an 8GB usb key to use to boot from instead. If you need instructions on how to create the USB installer with El Capitan or Yosemite on it - using your Macbook Pro of course. Then ask away.
I hope you get your iMac back on track. I had one of the same specs myself.
I have a ? ? Lion DL-DVD(which is my own copy that I kept after selling my iMac back then) that I can ship out should the need arise.
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Assuming you have it upgraded to a version of macOS, it's easy to create a USB install:
"How to create a bootable installer for macOS", https://support.apple.com/en-us/HT201372
"How to get old versions of macOS", https://support.apple.com/en-us/HT211683
And if you are interested in easily upgrading to something newer, you may want to check out:
http://dosdude1.com/software.html ...I've used these patchers successfully on many old machines (currently running Catalina on a 2009 mac mini, although a boot SSD is highly recommended).
whenever I try to image the usb installer on the drive it says that there has been an error and I've tried multiple times and I know its formatted correctly because I made it macOS extended (journaled)
I had a similar problem. I think mine was 2008.
You will need to start with the OS that was originally on the machine- was that Leopard or Snow leopard?
If you try a later version it won't work. Well it didn't for me.
You should have a functioning DVD drive on your 24" mac so you need to find some full installation disks from whatever the original OS was. Full disks not upgrade and that means they will not be grey they will have a picture on them.
Maybe you can borrow them off someone or if not, they are really cheap on Ebay. Maybe $10 or so?
Maybe someone here will lend you some if they live near you? I'm probably over the other side of the world.
Once you've got the original OS working then you can go online and download more recent versions. You may have to do this several times to get where you want although there's no harm in trying to skip to the latest supported version, but I don't think it'll let you.
I did this and it's the only way I could get it to work. USB didn't work on an old machine like that and from memory it was because you couldn't get Leopard on USB at the time.
Good luck. You will get it sorted out but it'll take a bit of time I'm afraid.
Additional: I've just checked and USB installation started with Sierra so your BIOS won't support it as I thought.
You will need to start with the OS that was originally on the machine- was that Leopard or Snow leopard?
If you try a later version it won't work. Well it didn't for me.
You should have a functioning DVD drive on your 24" mac so you need to find some full installation disks from whatever the original OS was. Full disks not upgrade and that means they will not be grey they will have a picture on them.
Maybe you can borrow them off someone or if not, they are really cheap on Ebay. Maybe $10 or so?
Maybe someone here will lend you some if they live near you? I'm probably over the other side of the world.
Once you've got the original OS working then you can go online and download more recent versions. You may have to do this several times to get where you want although there's no harm in trying to skip to the latest supported version, but I don't think it'll let you.
I did this and it's the only way I could get it to work. USB didn't work on an old machine like that and from memory it was because you couldn't get Leopard on USB at the time.
Good luck. You will get it sorted out but it'll take a bit of time I'm afraid.
Additional: I've just checked and USB installation started with Sierra so your BIOS won't support it as I thought.
For starters, what OS version would you like to image on the usb? Also, make sure you are running the instructions as an admin user. You might also check the usb is a gpt/guid partition type. They usually come default as mbr. Disk Utility can help you check that.
Im pretty sure that my dads Mac Pro came with the 10.5 install disc and he says he still has it so ill try with that and see if it works. I don't really need this iMac to work because I do have a MacBook, but then again my MacBook sucks and I don't have enough money to buy a new one. ill keep you posted if it works
I want to install 10.11 on the usb because it is the news version my iMac can officially support ( you can get up to 12.3 with patchers)
That's definitely your best bet.
It shouldn't take more than about 40 minutes or so and then you will be able to go into Apple and it will give you options for downloading later OS. As I say I've done it so I know it works.
I'm certain you won't be able to do it on USB as it didn't exist when your machine was made so you've no way to tell it to boot from USB in the BIOS
keep troubleshooting the usb thing, I’ve created many, many install media using Apples instructions. Usually if the process failed to create the media, it usually had to do with an improperly formatted USB stick (esp. wrong partition type) or a failing USB stick.
And I’ve never had to install an original OS on a machine in order to upgrade it to something newer (that’s compatible). Most of the time I upgrade old machines, I start with a cleanly wiped internal drive, no OS on it.
Just to further complicate things, the grey DVDs that come bundled with systems typically only work on the computer that they came with.
Please quote the error message.
So the discs didn't work. they make the iMac reboot constantly until it gets to a blank white screen and I again have no idea what to do. Do you think I could use a Mac Pro on 10.7 to make a new macOS install dvd? because I might be able to borrow a Mac to do that with but what version of macOS do I put on that dvd? I don't know if just doing a El Capitan disc will make it want to have a older version of macOS already on it, and would windows already being on there prevent the installation from succeeding? and if I can't borrow it is my iMac a lost cause? because I really want to have a AIO that works. Thanks for the help
It is on macOS 10.15.7. And while a do have a spare 40GB HDD, I do not have a USB connector to connect it to my MacBook or anything
Do you have a USB flash drive, 8gb or larger?
You will NEED one, so BUY one.
Do you have a copy of the El Cap installer, downloadable from Apple?
If you can't get it let us know.
You will also need either one of these small, free apps (I suggest you download both):
- DiskMaker X
- Install Disk Creator
Search for them and obtain them.
Be sure to download THE RIGHT VERSION for creating a bootable El Cap installer.
Now, use DiskMaker or Install Disk Creator to create the bootable USB flash drive, using the downloaded copy of the El Cap installer.
Then take it to the problem iMac and see if you can get booted.
You will NEED one, so BUY one.
Do you have a copy of the El Cap installer, downloadable from Apple?
If you can't get it let us know.
You will also need either one of these small, free apps (I suggest you download both):
- DiskMaker X
- Install Disk Creator
Search for them and obtain them.
Be sure to download THE RIGHT VERSION for creating a bootable El Cap installer.
Now, use DiskMaker or Install Disk Creator to create the bootable USB flash drive, using the downloaded copy of the El Cap installer.
Then take it to the problem iMac and see if you can get booted.