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macrumors newbie
Original poster
Jul 28, 2023
Hi folks, looking for help please, have an iMac mid 2007, trying to sell, needed to wipe clean and reset but have hit a wall. . Specs: 24 inch, 2.4 GHz Intel Core Duo, 4GB 667 MHz DDR2 SDRAM, ATI Radeon HD 2600 Pro 256 MB. Running OSX El Capitan V 10.11.6. Was working fine albeit very slow up until now.

Followed the instructions on the Apple website to wipe clean and re-install OSX via Recovery Mode. Attempted to erase HD in Disk Utility in Recovery Mode. Tried to erase top option / name of Computer in the side bar listing all the volumes which is a long serial no (Not Macintosh HD). Get an error message saying ‘couldn’t unmount disk’. Back in Disk Util go to 2nd option underneath this shows Macintosh HD. This can be erased. Erased using Mac OS Journaled, works fine. Side bar in Disk Util also shows under Disk Images category ‘Apple Disk Image Media’ and in next tier down ‘OSX Base System’. I mention this as next step is to reinstall OSX, but it looks like its still there!

Quit Disk Utility to Recovery Screen, picked re-install OSX. Process looks like its working fine, enter credentials hit ok, progress bar appears, takes approx 30 mins. Just when it looks like it’s finished it just reverts back to Recovery Screen, with Reinstall OSX showing again.

Followed online instructions via Apple website to try reinstall OSX using Bootable Installer. Went on my MacBook Pro and inserted a thumb drive, formatted to OSX Extended Journaled and named MyVolume, download OSX El Capitan to Applications Folder of MacBook, follow instructions to use terminal to create the Bootable Installer, however this fails on the MacBook Pro. I put in the command line as per Apple website for El Capitan which is -
sudo /Applications/Install\ OS\ X\ El\ --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\
It asks for password which I enter. Terminal says ‘command not found’.

Don’t know what to do next, now the iMac is stuck in recovery mode, I can’t install OSX! Please help.


macrumors member
Sep 21, 2012
FYI in case it offers any refinement of what you have been doing, are these instructions from MrMacintosh:

Internet Recovery Version​

If your Mac supports Internet Recovery, you can use this guide to find out which version of macOS you will get using the following options.

  • Newest OS – Option-⌘-R
This option will be the newest or latest version of macOS that can be installed on your Mac.

  • Shipping OS (Oldest OS Available) – Shift-Option-⌘-R
The “Shipping OS Version” is the macOS version that your Mac originally shipped with from the factory. This is the IR Version that you will see if you use Shift-Option-⌘-R.
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