Thank a Nerd: 2011 iMac Edition

Fixing a 13 year old iMac with a 8 year old operating system.

I've had a 2011 iMac sitting on the floor of my home office waiting to be sold / recycled for years now. It had worked fine up until I erased it to prepare for resale, and then when I tried to reinstall macOS the installer would always fail with this error message:

Photo of an iMac with "An error occurred while preparing the installation. Try running this application again." error on screen — "An error occurred while preparing the installation. Try running this application again."

Would you believe that when I tried running it again, it did the same thing? 😄

I'd googled for possible fixes in the past, but nothing had worked each time I tried. Then this weekend I was motivated to try one more time before sending it off to be recycled and stumbled on this YouTube video which lead me to this page that had the actual fix I needed:

In late December of 2023, I started an investigation as to why macOS High Sierra Internet recovery was broken. That’s not all, now macOS Sierra 10.12.6 Recovery & Internet Recovery are also broken! Keep in mind, the is NOT the date and time issue. This is different issue that can be reproduced every single time.

Thank Mr. Macintosh for Spending His Xmas Troubleshooting macOS Sierra

When I saw the published date on the blog post as being from January 14, 2024—this year!—I was very curious because most of the other fixes I'd tried were from 4+ years ago.

I elected to start with fix #3, "Download the ONLY working version of macOS Sierra from Apple to recovery and use it to install Sierra!", since it seemed the easiest to try.

I had to repeat the steps because I accidentally closed the Terminal window, killing the whole process half way through. But after the second walk through of the instructions, it worked and I had a successfully booting fresh install of macOS Sierra again.

An iMac on a table with a login screen for an admin account. — Hooray! Booted up fresh macOS Sierra on a 2011 iMac

As a result, I was able to sell it on Facebook Marketplace and send it off to a new home where someone else could use it for however long it lasts for them.

I really can't imagine a 2011 Windows PC still looking as good and running as well as this machine did. This was a 27" 2011 iMac with 2.7GHz i5, 16GB of 1333MHz RAM, and a Radeon 6770M with 512MB so not an entry level machine for it's time, but still.

So thank you Mr. Macintosh for wondering why an 8 year old operating system wasn't installing properly for people and taking the time to find 3 possible fixes! Nerds are awesome.