Download OS X El Capitan. In your Mac/existing Hackintosh/virtual machine running Mac OS X, open the Mac App Store app and download the latest version of OS X El Capitan. This is a 8 GB download, so it's probably going to take a while. Once the Mac App Store app finishes downloading OS X El Capitan, an update window will pop up. Download Mac OS El Capitan(Google Drive) Download Mac OS El Capitan(Utorrent) unlocker208. After the downloading finished, extract them then install VMware from here, that’s ok if you have installed before. Open Unlocker 208 then navigate to win-install and Run as Administrator. If you are on an earlier version of OS X, you can download and install El Capitan from directly the App Store. OS X El Capitan on Mac App Store. Alternatively, if you currently on a later version of macOS and want to downgrade to El Capitan for some reason, you can officially do so only if you have purchased it earlier. Macbook Pro 13' 2015 with OS X Yosemite on board. I've been trying to install OS X El Capitan, but always get the following message: 'This copy of the Install OS X El Capitan application can't be verified. It may have been corrupted or tampered with during downloading.' By the way this is not a date time issue, date is correct on my computer. Should you install the OS X El Capitan on your MacBook, iMac, Mac Pro or MacBook Air? We take a look at the new OS X 10.11.6 update and what's next.

Installing El Capiton on an old Mac Book Pro today, I received the error:

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 checked Apple’s support Matrix (it is a very old macbook pro) at https://support.apple.com/kb/SP728?locale=en_GB and it was listed as supported.

After lots of Googling and investigation, I discovered that the date and time were not set to current, the macbook thought it was year 2000.

You can easily reset the time and date by following the steps below:

Click Utilities on the menu bar
Select Terminal
Type date
Confirm the date is wrong
Type date 062112422016 (example: June 21st 12:42 2016)
Exit terminal
Click Restart

Once the Date and time are configured you will be able to install OS X.

Easy fix, for a ridiculous error!

To get the latest features and maintain the security, stability, compatibility, and performance of your Mac, it's important to keep your software up to date. Apple recommends that you always use the latest macOS that is compatible with your Mac.

Learn how to upgrade to macOS Big Sur, the latest version of macOS.

Check compatibility

The version of macOS that came with your Mac is the earliest version it can use. For example, if your Mac came with macOS Big Sur, it will not accept installation of macOS Catalina or earlier.

If a macOS can't be used on your Mac, the App Store or installer will let you know. For example, it might say that it's not compatible with this device or is too old to be opened on this version of macOS. To confirm compatibility before downloading, check the minimum hardware requirements:

macOS Catalina 10.15 hardware requirements
macOS Mojave 10.14 hardware requirements
macOS High Sierra 10.13 hardware requirements
macOS Sierra 10.12 hardware requirements
OS X El Capitan 10.11 hardware requirements
OS X Yosemite 10.10 hardware requirements

Download macOS using Safari on your Mac

El Capitan Did Not Install

Safari uses these links to find the old installers in the App Store. After downloading from the App Store, the installer opens automatically.

macOS Catalina 10.15 can upgrade Mojave, High Sierra, Sierra, El Capitan, Yosemite, Mavericks
macOS Mojave 10.14 can upgrade High Sierra, Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion
macOS High Sierra 10.13 can upgrade Sierra, El Capitan, Yosemite, Mavericks, Mountain Lion

Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.

El Capitan Reinstall

macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion, or Lion
OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion, or Snow Leopard
OS X Yosemite 10.10can upgrade Mavericks, Mountain Lion, Lion, or Snow Leopard

El Capitan Will Not Install