Mid-2011 A1311 won't USB boot.

[wunjee]

Okay, so I've got this mid-2011 iMac. I've replaced HDDs in these things several times in the past without issue. I replaced the HDD in this device with a Samsung Evo. When I power on the device and hold down the Alt-key (PC keyboard..) it boots to the boot device menu where it gives me the option to select a network and shows nothing else. I used TransMac to create an OS 10.12 image. It never shows up as a bootable device, even though I set the USB drive up as a GPT device. If I make a Windows bootable USB drive, it'll see that all day long and it'll allow me to boot off of that and start the Windows 10 install process..

It will not boot off of a MacOS bootable media, though.

Am I doing something wrong here? I've done this before with this exact process and honestly I don't know what I'm missing.

>Diskpart
>Select the disk
>Clean the disk
>Convert to GPT
>Set primary partition
>Open TransMac
>Format for Mac
>Restore DMG to the USB device

This process takes 10-15 minutes, and when I connect the USB device to the Mac, it never shows up as a boot device.

This is starting to irritate me.

 

[wunjee]

More weirdness.

I used my 2012 Macbook Pro to make a bootable 10.13 USB flash drive using the method described by Apple. It properly renamed the volume and copied the installer to the USB flash drive.

When I take that drive out and put it in the 2011 iMac, it is not detected as a bootable device.

Weirdly enough, when I connect the device back to my Macbook Pro and boot to the boot menu (hold Option after power-on) it still doesn't show there as a bootable device either. Even on the machine that made it..

I have no idea what's going on here.

 

[wunjee]

I ran through the steps again on my Macbook Pro - because the definition of insanity and all - and it actually gave me the option to boot from the media this time, but now when I try to boot from the media it loads for a few minutes and then gives a giant dark-grey circle with a line through it. No other prompts, no explanation, no nothing.

A quick search leads me to believe that this machine won't support 10.13 but I know it will.

Oh well. Will try 10.12 again tomorrow.

 

[Nguyen Duc Hieu]

If your iMac is still working fine, maybe you don't even need a USB installer at all.
You can do the Internet Recovery.

 

[wunjee]

If your iMac is still working fine, maybe you don't even need a USB installer at all.
You can do the Internet Recovery.

Internet recovery, without fail, fails. It almost immediately goes to a 24:00 clock and then about an hour later (without actually counting down any time) will go to a -2000 error. I read that this is because pre-2012 iMacs required a firmware update to continue using Internet Recovery at some point and this one (like many others) apparently never got it.

 

[wunjee]

I finally got it to work. The TransMac method just doesn't work at all. I was able to create bootable USB media from my 2012 Macbook Pro. But even then the first two times I created the media the process failed. The first time it wasn't bootable, the second time it was bootable but the loading process failed half-way through the initial bootup, and finally after the 3rd time of creating the boot media on the Macbook the boot media worked properly.