I have a new-to-me early-2009 iMac. It came to me without any updates since early 2016 and I decided to update it from OSX Yosemite to El Capitan (the last version supported on this hardware.)

I downloaded the "app" from the Store on the iMac and restarted to begin the installation process. During the install I receive the following message:

OS X could not be installed on your computer

No packages were eligible for install. Contact the software manufacturer for assistance. Quit the installer to restart your computer and try again.

I hit restart and I end up in a boot-loop. When I try to use the Alt (Option) key to select a recovery boot it just restarts back into the installer without giving me an option to select a boot source.

When I search for information about this error, I found suggestions to use the Terminal date command to set the correct timestamp. This does not appear to be the issue though as when I run the date command it returns the correct date and time (although the wrong timezone - PDT instead of the correct MDT).

Further research suggests I may have to use a bootable USB with the OS X installer on it. I do not, however, have any other Macs in my home. I have tried using TransMac but the drive doesn't seem to be recognized as a bootable device by the iMac.

Are there any other steps that I can try to make this work and escape this boot loop?


  • Google is your friend. "Create Bootable El Capitan USB Drive in Windows">>>>>>>jafty.com/blog/…
    – Moab
    Oct 25 '19 at 2:26
  • @Moab I followed those instructions (I linked to the SuperUser post that I followed). When I hold down the Alt Key (I only have a Windows keyboard) and click restart it does not appear in the boot selector. Oct 25 '19 at 2:32
  • 3
    You don't use date to set the correct date, you use it to set the date back to when the certificate was valid. sometime mid-2016 should be safe. Try that & tell us what happens. Alternatively, try Internet Recovery, Cmd/opt/R at the boot chimes. [Ah, I note that article was written in 2016, when its info was actually correct.]
    – Tetsujin
    Oct 25 '19 at 7:29
  • @Tetsujin that's the answer dude, post it in answeres not comments Oct 28 '19 at 5:18
  • I wasn't aware of this new message, so it was a guess. I've got a far more comprehensive Q&A over on Ask Different, for reference, to which I've now added this error message: apple.stackexchange.com/questions/309399/…
    – Tetsujin
    Oct 28 '19 at 10:52

I had to try multiple times but here I'm with my solution. I was trying to factory reset a MacBook Pro 13-inch Retina from Early 2015 with OS El Capitan.

The problem was that today is is a day in March 2020.

The solution was:

  1. Plug your computer to internet through an ethernet cable.
  2. Power up your Mac and press Cmd + R
  3. Setup starts, format your main HD and rename it Macintosh HD or whatever name you prefer
  4. After this operation exit the Disk Utility and open up a terminal, type date and look at the date of today: you will see the date of today, then type date 101615072016: and thanks to this command you have changed the date to 2016.

enter image description here

  1. Now start installing your OS. The internet connection will download some files. Then you will see this image, click "continue" so the computer will verify the certificate.

enter image description here

  1. Then you will now see this image. Open the terminal again, set again the date to date 101615072016 becasue the internet connection has changed that back to your current date and unplug the ethernet cable.

enter image description here

  1. Click continue and you are now good to go.

Keep in mind that for every OS you might need to set the right date: These examples below set the date to one day after the official release date of each version. The date format is mmddHHMMyyyy (month-day-hour-minute-year)

  • OS X 10.11 (El Capitan): date 100123452015 for Thu 1 Oct 2015 23:45:00
  • macOS 10.12 (Sierra): date 092123452016 for Wed 21 Sep 2016 23:45:00
  • macOS 10.13 (High Sierra): date 092523452017 for Mon 25 Sep 2017 23:45:00
  • macOS 10.14 (Mojave): date 092523452018 for Tue 25 Sep 2018 23:45:00
  • This worked for me! (Setting up a vintage 2012 MacBook Pro with El Capitan after I had erased the hard drive.) Thank you!
    – larapsodia
    Mar 25 '20 at 10:39

October 2019

Apple have now released new certificate versions of the last 6 major OS versions, Catalina right back to Yosemite.

This means you no longer need to change the date to install.

Apple KB - If an installer says it can't be verified or was signed with a certificate that has expired

This contains links to further KBs for each of the 6 most recent OSes from Catalina back to Yosemite.

The three newer ones link to the App Store, but Sierra, El Capitan & Yosemite link to direct downloads.

  • Two notes: 1) Those direct downloads are for upgrades only. They will not install onto a blank disk with no version of macOS on it. 2) I just redownloaded the El Capitan installer (the real one, from the App Store) today and it still gave me the "No packages were eligible to install" error. I verified that the installer had a valid certificate. Changing the date to September 2019 fixed the problem.
    – Calion
    Nov 7 '19 at 2:40
  • Fast forward to december 2019... Downloading El Capitan (from list of my previously downloaded apps in app store) actually required backdating the system clock to mid 2016(!) in order to complete the installation as @Tetsujin mentions.
    – Claudijo
    Dec 18 '19 at 8:46

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