Type date into Terminal followed by today’s date in this format so today is July 11, 2016, 2:15 that would be date 0711141516 then press enter.Type date into Terminal and hit enter this displays the date if it is not the current date, you need to go to the next step.Once booted into recovery, choose Utilities from the menu and then Terminal.Power up and hold the Option key down as soon as you hear the startup chime.Insert a USB key with OS X install into Mac (or install disc).Here are some simple steps to change the OS X system date from Terminal when doing a fresh install. Try running again.” At this point, many people will throw in the towel and figure the computer is toast. More often than not, you’ll get an error that reads, “An error occurred while preparing the installation. We hold no responsibility for any damage following this guide may cause. Please use with caution and understand that whatever you do to your Mac is on you. UPDATE: This article is dated and may not be relevant to your version of macOS. Often the system date on neglected Macs gets reset to the year 2001, which prevents you from reinstalling OS X, but you can get this done through Terminal. If you’ve left your Mac lying around for a very long time or if you bought a used one, the system date may be out of whack.
