Can't Reinstall MacOS El Capitan on Early 2009 iMac

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Level 1

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Can't Reinstall MacOS El Capitan on Early 2009 iMac

I've wiped the HDD and now want to reinstall MacOS 10.11 onto my Early 2009 24" iMac. It runs perfectly, has upgraded RAM and a new 2TB fusion drive. When using the Restore menu, I select reinstall MacOS. It spent 45 minutes downloading the OS image and restarted. Then it opened a dialog that said it could not install MacOS because there were no eligible packages. Restarting causes the same error message.

I'd like to get my computer working again. Anyone seen this error? Not sure how to proceed here...

Mahalo

iMac, OS X 10.11

Posted on Mar 14, 2020 7:59 PM

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Answer 1

Kappy

Level 10

361,741 points

Mar 15, 2020 11:25 AM in response to Maui Boy

No, your new iMac is not supported by El Capitan. I think Mojave is the earliest version the iMac can run. You can make a bootable USB flash drive, however, on the new iMac. Use this link: Download OS X El Capitan. A file named InstallMacOSX.dmg will download to your Mac.

First, review this introductory article: Create a bootable installer for macOS. Second, read this How To outline for creating a bootable macOS installer. Simply use the Terminal command by copying and pasting the command line for the version of macOS from the list below. You will need an 8GB or larger USB flash drive that has been partitioned and formatted for use with OS X as well as an installer for the desired macOS version that you have previously downloaded from the App Store.

Drive Partition and Format

Open Disk Utility in the Utilities' folder.
After Disk Utility loads select the drive (out-dented entry with the mfg.'s ID and size) from the side list.
Click on the Erase tab in the Disk Utility toolbar. Name the drive, "MyVolume". <---- IMPORTANT!
In the drop down panel set the partition scheme to GUID. Set the Format type to Mac OS Extended (Journaled.)
Click on the Apply button and wait for the Done button to activate. When it does click on it.
Quit Disk Utility.

Create Installer

Open the Terminal in the Utilities' folder. Choose the appropriate command line (begins with "sudo") depending upon what OS X installer you want. I've bolded the command for El Capitan. Paste that entire command line from below at the Terminal's prompt:

Command for macOS Catalina:

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Command for macOS Mojave:

sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Command for macOS High Sierra:

sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Command for macOS Sierra:

sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ macOS\ Sierra.app

Command for El Capitan:

sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

Command for Yosemite:

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Yosemite.app

Command for Mavericks:

sudo /Applications/Install\ OS\ X\ Mavericks.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Mavericks.app

Press RETURN. You will be asked for your admin password. It will not echo to the Terminal window. Then press RETURN again. Wait for the return of the Terminal prompt signifying the process has completed. It takes quite some time to finish. Be patient.

The bootable installer can be used to install the selected version of macOS. Shut the computer down. Insert your flash drive into a USB port. Start the computer like so:

Boot Using OPTION key

Restart the computer.
Immediately after the chime press and hold down the "OPTION" key.
Release the key when the Boot Manager screen appears.
Select the disk icon for the USB flash drive.
Click on the arrow button under the disk icon.

I don't know what you downloaded as the El Capitan installer but I have provided the link earlier in this post. The download is a disk image file with a ".dmg" extent or filetype. It will download to your Downloads folder, so make a copy in the Applications folder.

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Answer 2

Kappy

Level 10

361,741 points

Mar 14, 2020 8:19 PM in response to Maui Boy

How to upgrade to OS X El Capitan - Apple Support

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Answer 3

Maui Boy Author

Level 1

4 points

Mar 14, 2020 10:59 PM in response to Kappy

Thanks for the link. I've read it through and the only option appears to be to create a bootable installer. However, as I've downloaded the El Capitan installMacOSX.pkg installer, it will not run on my new iMac.

I've used pkgutil --expand to open the installer pkg on the .dmg image. Then, rooting around to find the Payload, cpio -iv to unpack it. In the results is the Install El Capitan.app.

Running createinstallmedia from within the Resources in the .app, it claims the Install El Capitan.app is not a valid os installer application.

It may be that the normal .pkg installer would mark the image in some way after installing it in the /Applications folder, or perhaps I inadvertently corrupted the .app when extracting it.

Am I on the right track or is there a simpler way to do this?

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Answer 4

Maui Boy Author

Level 1

4 points

Mar 15, 2020 8:55 AM in response to Maui Boy

Here is the error I'm getting:

"./Install OS X El Capitan.app does not appear to be a valid OS installer application."

Any ideas on how I might get through this issue? Here are some thoughts I had, but not sure how to proceed...

Is this a problem with the El Capitan createinstallmedia being incompatible with the new iMac or Catalina?

If so, can I use the createinstallmedia executable from the OS on the new iMac to prepare the El Capitan install media by referencing the 'Install OS X El Capitan.app'?

If this will work, where can I find the "createinstallmedia" executable on the new iMac that has Catalina running? The machine came with Catalina already installed so I don't have media or a package with the installer.

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Answer 5

Maui Boy Author

Level 1

4 points

Mar 15, 2020 2:53 PM in response to Kappy

Thank you for the detailed instructions. I must say though that I went through this procedure already, and posted my results last night. The “createinstallmedia” step fails.

The download link I used is the same one you posted.

However, the downloaded file is a .DMG, which is a disk image, not an application package. It is necessary to mount the image, then open the InstallMacOS package file, using the terminal command line. And that package is just an installer of the installer: it only moves the actual OS installer application into the Applications folder. It has to be unpacked with pkgutil to get to the true OS installer .app which is buried in the Payload which must then be expanded into a new folder with cpio. The createinstallmedia program is within the Resources of this embedded application package that is revealed by cpio.

As near as I can tell, the createinstallmedia command line program is not compatible with the new iMac, though it does run, it produces an error that the application is not an OS Installer Application. Perhaps the application installer might somehow mark the OS installer application to make it valid. And since the app installer can’t be run on the new iMac, this process may not work the way it used to.

What I’m wondering is if I can use the createinstallmedia program from a newer OS package that is compatible with this new iMac to prepare install media with the El Capitan OS install app. I may try this later.

Otherwise, I may have to take the machine into the Apple store, after they reopen from the COVID-19 lockdown. The Apple store maintenance folks no doubt have install media already prepared.

I’m grateful for your time and attention! And I am open to any other suggestions!

Mahalo

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Answer 6

Kappy

Level 10

361,741 points

Mar 15, 2020 8:56 PM in response to Maui Boy

I have used those command lines many times in different versions of macOS. If you wish to try something different, then download DiskMaker X9.0. It is 32-bit and 64-bit compatible and works with 10.10.0 and later.

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Answer 7

Maui Boy Author

Level 1

4 points

Mar 15, 2020 9:14 PM in response to Kappy

Thanks Kappy, really, for stepping in to help. The problem is that I can’t install the El Capitan application. And I’ve tried extracting the InstallESD as suggested by by DiskMaker. Disk Maker requires an installed OS Install Application, not just the download package. And they are clear to get that I must first run the downloaded installer before extracting the InstallESD.dmg. And this can only be done on a Mac that is compatible with El Capitan. The image as delivered to Catalina is not usable by Disk Maker or Apple’s Disk Utility.

My last untried option is to use Unix tools to DD the ESD image onto an external drive. DD will copy anything, block by block.

If that doesn’t work, then unless Apple has El Capitan media at their maintenance shop, I think this computer is now a brick.

Thanks

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Can't Reinstall MacOS El Capitan on Early 2009 iMac

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