Stuck clean installing High Sierra

[JRD.ABQ.Mid2011imac.]

Hello. I’ve broken down and am reaching out to anyone that can help me. I found a video on YouTube that walks you through the process of downloading High Sierra and then the installer, copy and paste to the terminal, I used a Samsung 1Tb SSD and followed the steps as shown and I got all the way past erasing my HD, with a time machine back up on ssd along with installer and got to the installation process and it got stuck saying “ installation in progress, calculating remaining time” and believe it froze up. I gave it several hours. So now my Imac is and has been shut down since. Now what do I do?? Restart in recovery mode? Then what? Everything is as it was. PLEASE HELP!!!

not exactly related to the above but

I also have some error messages/code if anyone can decrypt it per say. Thank you. Jon

 

[TonyAguila]

Hello. I’ve broken down and am reaching out to anyone that can help me. I found a video on YouTube that walks you through the process of downloading High Sierra and then the installer, copy and paste to the terminal, I used a Samsung 1Tb SSD and followed the steps as shown and I got all the way past erasing my HD, with a time machine back up on ssd along with installer and got to the installation process and it got stuck saying “ installation in progress, calculating remaining time” and believe it froze up. I gave it several hours. So now my Imac is and has been shut down since. Now what do I do?? Restart in recovery mode? Then what? Everything is as it was. PLEASE HELP!!!

not exactly related to the above but

I also have some error messages/code if anyone can decrypt it per say. Thank you. Jon

That was a good move creating a Time Machine backup beforehand! Getting instructions from a YouTube video, not very good . You should have come here (Mac Help) instead. In future, it will also be very helpful if you were to supply your Mac’s model identifier (About This Mac -> System Report…).The model ID will be the second line under Hardware Overview.

So onto the repair. It will be a good precaution if you did a SMC reset. The steps differ with different Macs but you can easily Google the method for your machine. After the SMC reset, from a cold start, boot up and immediately hold down command-R. This assumes that you are connected to the internet. When Recovery comes up, go into Disk Utility and erase the drive. If it was running Mojave or newer, I recommend using APFS as the format. Next, exit Disk Utility to get to the main menu. Select install/reinstall macOS (at this point Recovery will only offer the newest version that your Mac can run). Proceed. If the installation was successful, the next step is to migrate your data to the new system. Select Time Machine (I assume it is already connected). The default settings should be okay, unless you see options that you don’t wish to migrate (e.g., a second user). And there you go! Good luck.

Come back if the system installed is newer than High Sierra and you are still determined to run High Sierra instead. Downgrading is usually more tricky, which was probably the reason your previous effort did not work. And I’m suspicious of the High Sierra installer you downloaded. You are better off downloading from the Apple Support area.

 

[JRD.ABQ.Mid2011imac.]

That was a good move creating a Time Machine backup beforehand! Getting instructions from a YouTube video, not very good . You should have come here (Mac Help) instead. In future, it will also be very helpful if you were to supply your Mac’s model identifier (About This Mac -> System Report…).The model ID will be the second line under Hardware Overview.

So onto the repair. It will be a good precaution if you did a SMC reset. The steps differ with different Macs but you can easily Google the method for your machine. After the SMC reset, from a cold start, boot up and immediately hold down command-R. This assumes that you are connected to the internet. When Recovery comes up, go into Disk Utility and erase the drive. If it was running Mojave or newer, I recommend using APFS as the format. Next, exit Disk Utility to get to the main menu. Select install/reinstall macOS (at this point Recovery will only offer the newest version that your Mac can run). Proceed. If the installation was successful, the next step is to migrate your data to the new system. Select Time Machine (I assume it is already connected). The default settings should be okay, unless you see options that you don’t wish to migrate (e.g., a second user). And there you go! Good luck.

Come back if the system installed is newer than High Sierra and you are still determined to run High Sierra instead. Downgrading is usually more tricky, which was probably the reason your previous effort did not work. And I’m suspicious of the High Sierra installer you downloaded. You are better off downloading from the Apple Support area.

Tony- Thank you. I updated info. I have not powered it up yet....I assume I need to go straight into a recovery mode or something...LMK if that helps you out to understand better

 

[TonyAguila]

Tony- Thank you. I updated info. I have not powered it up yet....I assume I need to go straight into a recovery mode or something...LMK if that helps you out to understand better

Okay, your iMac model ID is either iMac12.1 (21.5") or iMac12.2 (27"). The maximum OS is macOS 10.13.6 (High Sierra). If you have an up-to-date Time Machine backup, you can choose to go into Recovery and reformat your startup drive and perform a clean install of macOS. Afterwards, you can migrate your data from Time Machine.

If you don’t have a reliable Time Machine backup, and are confident in the data in the current drive, you can skip the disk erasure, and just reinstall macOS. Recovery should default to installing High Sierra, unless Apple has certified your Mac model for a newer macOS version.

 

[JRD.ABQ.Mid2011imac.]

T

Okay, your iMac model ID is either iMac12.1 (21.5") or iMac12.2 (27"). The maximum OS is macOS 10.13.6 (High Sierra). If you have an up-to-date Time Machine backup, you can choose to go into Recovery and reformat your startup drive and perform a clean install of macOS. Afterwards, you can migrate your data from Time Machine.

If you don’t have a reliable Time Machine backup, and are confident in the data in the current drive, you can skip the disk erasure, and just reinstall macOS. Recovery should default to installing High Sierra, unless Apple has certified your Mac model for a newer macOS version.

Thanks! Yea its the 21.5 and I am fairly confident that back up ok. I already erased the HD. Not sure what apple will default me to as when the next OS came out I was able to upgrade/update it but I had issues with password settings and a couple other things and apple recommended me to go back to HS. This was years ago and been running since.
Prior to doing the last steps I did, downloading the installer, via copy and paste to the terminal I did a diagnostic test and I got back a code. Apple wont revile what it means and can’t find it on the WWW. Something tells me it may have to do with the memory.. As follows: 4MEM/9/40000000:0x8873d398
So should I follow your instructions? Do I need an installer if I erase again?
Thanks for everything so far!!!

 

[TonyAguila]

T

Thanks! Yea its the 21.5 and I am fairly confident that back up ok. I already erased the HD. Not sure what apple will default me to as when the next OS came out I was able to upgrade/update it but I had issues with password settings and a couple other things and apple recommended me to go back to HS. This was years ago and been running since.
Prior to doing the last steps I did, downloading the installer, via copy and paste to the terminal I did a diagnostic test and I got back a code. Apple wont revile what it means and can’t find it on the WWW. Something tells me it may have to do with the memory.. As follows: 4MEM/9/40000000:0x8873d398
So should I follow your instructions? Do I need an installer if I erase again?
Thanks for everything so far!!!

Jon, I recommend that you go ahead with the installation via Recovery. I’d say go with High Sierra unless Recovery brings up a newer macOS version. At that point, why not try a newer version anyway if offered? If you end up with HS and the installation worked, the original copy of the HS installer would be suspect. I would trash it and plan on getting another copy from the Apple Support web site (I can give you the link later), or use the App Store to get a fresh copy.

Always have a good copy of the system installer and the latest combo updater/security update handy.

By the way, that error code comes back to a hardware error specific to the iMac, in connection with RAM modules. You may want to reseat your modules if you have direct access to them.

iMac harware error code 4MEM/9/40000000 - Apple Community

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