Try Again (BlackMambaJesus) Mac OS
Issue
Delete them, then reboot your Mac and try to download macOS Big Sur again. And, if that doesn’t work, try opening the App Store and clicking ‘View My Account’ to see if there is anything in. Apr 06, 2021 Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue. Mar 18, 2021 Begin by restarting your Mac. When your computer is about ready to pull up the black loading screen, press the Option + Command + P + R keys simultaneously. Keep holding those four keys down until. Jul 24, 2018 Now go back to the utilities window (install screen) and try again. The problem may be that your Mac is trying to install a version of OS that was last installed on this particular computer. This may be an issue especially if this is a second had, used Mac. Please follow these steps: Start up your Mac in Internet Recovery Mode.
Installing Mac OS X on iMac's blank formatted hard drive. Installation runs for 5-10 minutes and then fails with following error:
An error occurred while preparing the installation. Try running this application again.
Tried installing OS X El Capitan (10.11) and OS X Sierra (10.12) - the same error occurs in both cases.
Resolution
Issue was resolved by fixing incorrect time on the iMac and then clearing NVRAM.
Fix incorrect time
- Boot from Mac OS X installation disk / USB.
- Go to Utilities > Terminal.
- Type date to check the current date and time.
- If it's incorrect, run following to fix the date and time: date mmddHHMMyyyy
Where: mm - month, dd - day, HH - hour, MM - minute, yyyy - year
Clear NVRAM
- Shut down the Mac
- Start the Mac and as soon as you hear startup chime press and hold keys Command + Option + P + R.
- Keep holding the keys until Mac reboots and you hear another startup chime.
iMac 21.5' (2009)
Mac OS X El Capitan (10.11)
Mac OS X Sierra (10.12)