I aquired this unit with a bad hard drive. I installed a new SSD which I converted to GPT in Diskpart. The iMac created two partitions on the SSD, one is only 16MB, the other is the remainder of the 1TB. I have tried to install both High Sierra and Lion to no avail. I keep getting the folder with the question mark on boot up. Ran diags and only thing it found was HD temp sensor error. What am I doing wrong here? When I try internet recovery, it gets halfway through installing Lion and reboots. My first foray into the Apple world. Been a PC Tech since the 8088s vame out back in the 80s. I fix laptops, phone, and flat screen TVs as a hobby. IO know I am just not doing something right...Any assistance will be greatly appreciated!!
IMac 2011 A1312
- Thread starter ljintexas
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Cory Cooper
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Hello and welcome.
The temp sensor error can be resolved a couple of ways - OWC sells the In-line Digital Thermal Sensor for all Apple iMac 2011 Models, which is on sale for $32.99 USD currently. There is also a YouTube video that discusses another option, since they believe the OWC option is a money grab: The OWC 2011 IMac Sensor cable controversy.
The best way to install OS X/macOS from scratch on an older Mac is with a USB flash drive installer:
Create a bootable installer for macOS
How to download macOS
Also, third-party RAM has been known to cause install issues...do you have the original Apple OEM RAM, or has it been upgraded with third-party modules?
Hope that helps!
C
The temp sensor error can be resolved a couple of ways - OWC sells the In-line Digital Thermal Sensor for all Apple iMac 2011 Models, which is on sale for $32.99 USD currently. There is also a YouTube video that discusses another option, since they believe the OWC option is a money grab: The OWC 2011 IMac Sensor cable controversy.
The best way to install OS X/macOS from scratch on an older Mac is with a USB flash drive installer:
Create a bootable installer for macOS
How to download macOS
Also, third-party RAM has been known to cause install issues...do you have the original Apple OEM RAM, or has it been upgraded with third-party modules?
Hope that helps!
C
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I suspect the problem is with using Diskpart. I suggest using Disk Utility to format the SSD, if you have access to a running Mac, or if you can boot the iMac in Recovery. The maximum macOS version the 2011 iMac can run is High Sierra. Even though APFS was not introduced until 2017 with the release of High Sierra, I still recommend that you format the SSD as APFS, default setting, single partition, and maybe give it the default name, Macintosh HD.
It will probably be less tricky to install High Sierra using a newer Mac, but if your iMac is capable, you should be able to install macOS High Sierra directly using Recovery if you have an internet connection. Recovery should default to installing High Sierra on your 2011 iMac. It might offer a newer version if you were to run Recovery from a newer Mac though. Just remember that the 2011 iMac will not work with macOS newer than High Sierra.
It will probably be less tricky to install High Sierra using a newer Mac, but if your iMac is capable, you should be able to install macOS High Sierra directly using Recovery if you have an internet connection. Recovery should default to installing High Sierra on your 2011 iMac. It might offer a newer version if you were to run Recovery from a newer Mac though. Just remember that the 2011 iMac will not work with macOS newer than High Sierra.