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An error occurred while preparing the installation...

Hi,


I have a MacBook Late 2008. I have an SSD installed and I want to install El Capitan but it keeps failing. I don't have the HDD that was in the MacBook before hand. I can boot to OSX Utilities and then get an error that says "An error occurred while preparing the installation. Try running this application again."


Things I have tried without success:-

  • Restarting and trying to install again - tried this six times
  • Reseting the PRAM and NVRAM
  • Ran Disk Utility - first aid on the SSD (everything's fine)
  • Changing the time and date using Terminal to January 15, 2017, also tried a random date in 2016.)
  • Created a bootable USB but get the error " This version of El Capitan cannot be verified." I tried to download El Capitan from the App Store but I can't.
  • Tried to install on a WiFi network with no other traffic.
  • Using my Time Machine HDD to connected to it to see if some how that will do something.


Things I've done with success: -

  • Kept my sanity.


All help will be appreciated. Please let me know if there's more details I can help with.


Thanks


Phil

MacBook, OS X 10.11

Posted on Apr 12, 2020 11:53 AM

Reply
Question marked as Top-ranking reply

Posted on Apr 12, 2020 1:21 PM

In order to install El Capitan from the Apple Recovery Servers it would be better to get your mac connected by cable rather than WiFi. I don't think Apple have bothered to update the certificates on their recovery software, so try changing the date in Terminal again, another reason for using a cabled connection is that WiFi has the habit of changing the date back to today.

So if your only alternative is to download El Capitan through the recovery servers, hitch your mac up to the internet via a cable.

Restart into your Recovery HD, make sure the WiFi is off, reset the date and time in Terminal.


Enter a new date, for example or just copy and paste


sudo date -u 011421002016


press Return

enter your password

press Return


If Terminal returns an error saying sudo : command not found, then try again without sudo.


OR:

Do you still have an operating system on your mac, if so just boot to that and download El Capitan from here,

How to upgrade to OS X El Capitan – Apple Support (this has the updated certificates)

Go to Section 4 and click on Download OS X El Capitan, this downloads InstallMacOSX.dmg to your downloads folder.

When it has downloaded double-click on it and it will open to InstallMacOSX.pkg. Double-click on that and an installation window will open, this does not install El Capitan but uses InstallMacOSX.pkg to create Install OS X El Capitan.app in your Applications folder. Double-clicking on that will start the installation procedure.


OR:

If you can't use your mac to do this, then you could download El Capitan to another mac. This mac must be able to run El Capitan or have been able to run El Capitan at one time. Any mac that came preinstalled with an OS newer than El Capitan cannot do this. If you have or can borrow a mac that meets the requirements then you can download as mentioned above, follow the procedures to get Install OS X El Capitan.app in the Applications folder. Having done that plug in a USB stick (8GBs or larger) and create a bootable USB installer using the createinstallmedia command in Terminal.

How to create a bootable installer for macOS – Apple Support

Once you have created the bootable USB installer then you can plug that in to your original mac.

Restart the mac whilst pressing and holding the option/ alt key, in a couple of minutes the mac should boot to the Startup Manager, where you will see the bootable drives available, the USB should be on the right, select it and press Return.

The mac will now restart and boot to the bootable USB installer. Upon boot you will see a Utilities panel select Install OS X

and press Continue.

Similar questions

6 replies
Question marked as Top-ranking reply

Apr 12, 2020 1:21 PM in response to PhilR85

In order to install El Capitan from the Apple Recovery Servers it would be better to get your mac connected by cable rather than WiFi. I don't think Apple have bothered to update the certificates on their recovery software, so try changing the date in Terminal again, another reason for using a cabled connection is that WiFi has the habit of changing the date back to today.

So if your only alternative is to download El Capitan through the recovery servers, hitch your mac up to the internet via a cable.

Restart into your Recovery HD, make sure the WiFi is off, reset the date and time in Terminal.


Enter a new date, for example or just copy and paste


sudo date -u 011421002016


press Return

enter your password

press Return


If Terminal returns an error saying sudo : command not found, then try again without sudo.


OR:

Do you still have an operating system on your mac, if so just boot to that and download El Capitan from here,

How to upgrade to OS X El Capitan – Apple Support (this has the updated certificates)

Go to Section 4 and click on Download OS X El Capitan, this downloads InstallMacOSX.dmg to your downloads folder.

When it has downloaded double-click on it and it will open to InstallMacOSX.pkg. Double-click on that and an installation window will open, this does not install El Capitan but uses InstallMacOSX.pkg to create Install OS X El Capitan.app in your Applications folder. Double-clicking on that will start the installation procedure.


OR:

If you can't use your mac to do this, then you could download El Capitan to another mac. This mac must be able to run El Capitan or have been able to run El Capitan at one time. Any mac that came preinstalled with an OS newer than El Capitan cannot do this. If you have or can borrow a mac that meets the requirements then you can download as mentioned above, follow the procedures to get Install OS X El Capitan.app in the Applications folder. Having done that plug in a USB stick (8GBs or larger) and create a bootable USB installer using the createinstallmedia command in Terminal.

How to create a bootable installer for macOS – Apple Support

Once you have created the bootable USB installer then you can plug that in to your original mac.

Restart the mac whilst pressing and holding the option/ alt key, in a couple of minutes the mac should boot to the Startup Manager, where you will see the bootable drives available, the USB should be on the right, select it and press Return.

The mac will now restart and boot to the bootable USB installer. Upon boot you will see a Utilities panel select Install OS X

and press Continue.

Apr 16, 2020 9:15 PM in response to Eau Rouge

Hi Eau Rouge,


Thank you for your advice. I tried parts of what you suggested and a few other things from other sources too and eventually got my El Capitan installed. Here's what I did: -


  • Created an El Capitan USB stick as per the last suggestion in your post with another computer.
  • On my machine I started into OSX Utilities by holding down option at startup and booting to the USB stick.
  • I connected to my WiFi network.
  • I then checked the date and time in Terminal by typing "date." I'm not sure if I needed to do this but did it anyway. The date was the present day, so I put the date back to 2017 as per this video: https://www.youtube.com/watch?v=awUYJIUYzTU
  • Once the date was changed I closed Terminal and restarted.
  • I booted into the Recovery USB again and once at OSX Utilities I selected install OSX.
  • The install worked no problem.


Thanks for your help!!

Apr 16, 2020 9:36 PM in response to PhilR85

If you download El Capitan on another mac and created a bootable USB, the  version of El Capitan

has the new certificates so there was no need to reset the date back in Terminal.

There was no need to restart after changing the date in Terminal,

I said not to use WiFi, it tends to reset the date back to today, but that wouldn't have mattered as

you didn't need to change the date anyway as you were installing from the USB.

You would only have needed to reset the date if you were attempting to install El Capitan from

Apples Recovery Servers, the copy of El Capitan on the Recovery Server has not had its certificates updated

thus the need to change the date.

An error occurred while preparing the installation...

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