iMac Monterey Rescue Disc tries to install El Capitan

[osxhero]

So, I came home to my trusty iMac Dec 2015 machine, and found it with a flashing folder and the omnius blinking ?.

The computer was running when it transitioned into this mode, so could be the drive, could be something deeper.

However, I was able to boot to either the internal recovery disk OR the internet recovery disk.

I ran Disk Utility on my internal drive, which passed with flying colors. I swapped the memory out to ensure that wasn't causing the problem.

When I attempt to Reinstall the OS, even though it's on Monterey, it tries to install El Capitan. Given that the internal Firmware prevents this, it fails.

Is there a way to Telnet this over to Monterey?

Any other advice?

My new Mac Mini fully loaded arrives on Thursday. It wasn't supposed to be a replacement, just good timing.

Thank you!

 

[CoastalOR]

However, I was able to boot to either the internal recovery disk OR the internet recovery disk.

I ran Disk Utility on my internal drive, which passed with flying colors. I swapped the memory out to ensure that wasn't causing the problem.

When I attempt to Reinstall the OS, even though it's on Monterey, it tries to install El Capitan. Given that the internal Firmware prevents this, it fails.

Is there a way to Telnet this over to Monterey?

Any other advice?

Exactly what recovery mode are entering, internal recovery disk OR the internet recovery? What key combination to enter recovery?

It sounds like you are in internet recovery since it is offering on El Capitan (the macOS that originally shipped with your late 2015 iMac. The problem is the El Capitan installer can not the APFS drive format used for Monterey.

I think you need internet recovery that offers the latest macOS for your supported iMac (Monterey).
"On an Intel-based Mac, if you use Option-Command-R during startup, you might be offered the latest macOS that is compatible with your Mac."

How to reinstall macOS - Apple Support

You can use macOS Recovery, your computer's built-in recovery system, to reinstall the Mac operating system. Reinstalling macOS doesn't remove your personal data.

support.apple.com

 

[osxhero]

Exactly what recovery mode are entering, internal recovery disk OR the internet recovery? What key combination to enter recovery?

It sounds like you are in internet recovery since it is offering on El Capitan (the macOS that originally shipped with your late 2015 iMac. The problem is the El Capitan installer can not the APFS drive format used for Monterey.

I think you need internet recovery that offers the latest macOS for your supported iMac (Monterey).
"On an Intel-based Mac, if you use Option-Command-R during startup, you might be offered the latest macOS that is compatible with your Mac."

How to reinstall macOS - Apple Support

You can use macOS Recovery, your computer's built-in recovery system, to reinstall the Mac operating system. Reinstalling macOS doesn't remove your personal data.

support.apple.com

Sadly, both internet and internal go for El Capitan.

That being said, I've used the Monterey OS inside my recovery partition on BOTH for years. I'm a developer and often will use these to ensure the health of my drives.

I was really surprised it defaulted to El Capitan.

 

[osxhero]

Okay, crazy update:

I rebooted for the 10th plus time. CMD-OPT-R, got prompted for the internet boot, entered my credentials, booted to Monterey recovery! Wha???

I immediately opted to install Monterey on one of my many external drives, but then it said I needed to offer internet access. Didn't I just boot on the internet?

Anyway, I entered the network password, started the install, and now it's moving the files to the drive.

I've never seen anything like this since 2001.

 

[DeltaMac]

If it defaults to El Capitan, then that really sounds like the internal drive has failed, meaning that the recovery partition is also gone. When THAT happens, then you may believe that your Mac is booting to the recovery partition, when it actually bypasses that and boots to internet recovery, which would explain the El Capitan - offering the system version that your iMac originally shipped with.
Do you have a fusion drive? likely that the hard drive has failed, so you are only left with the SSD part, which might test good, but the loss of the HDD means that the fusion drive set is gone, too.

Now, I see that you have booted to recovery offering you Monterey. Hope that works for you.
Still curious -- do you have a fusion drive?

 

[Bigwaff]

Wouldn't normal Recovery fallback to Internet Recovery display the spinning globe?

 

[osxhero]

It's definitely the drive. I was able (spontaneously) to boot from Monterey Internet recovery. It failed more than 10 times prior. Randomly, it worked! I was able to install Monterey on an external drive.

SURPRISE! It erases your drive without notice. So, I lost 3TB of data that I now I have to send off to get a backup drive to restore.

Apple is really slipping. They used to warn you.