There have been a number of reports of people having issues with macOs High Sierra, so Apple has released a guide for iMac Pro owners who need a little help. One such issue is that has been documented is the iMac Pro becoming totally unresponsive if you lose power during a software update. If this has happened to you, all is not lost. You’re just going to need to restore your iMac Pro. To do this, the first thing you’ll need to do is put the computer into Device Firmware Update (DFU) mode. Then you’ll need to have access to another Mac that has the newest version of High Sierra, including Apple Configurator 2.6. And as for connecting it all together, you’ll need a USB-A to USB-C or Thunderbolt to USB-C cable.
Once you have everything ready, you can follow these steps:
- Power on the second Mac.
- Make sure your second Mac has the latest High Sierra version.
- If iTunes is running, close it.
- Open Apple Configurator and make sure it is version 2.6.
- Plug in your USB or Thunderbolt cable into the second Mac.
- Power down and unplug your iMac Pro.
- On your iMac Pro, plug the cable in the Thunderbolt port that is right next to the Ethernet port.
- Press and hold the power button on the iMac Pro.
- While still holding the power button, plug your iMac Pro back in and then continue holding the power button for 3 seconds. You shouldn’t see anything on the screen just yet.
- On the second Mac, in the Device Browser of the Apple Configurator, click on the iBridge device.
- Click on “Action”.
- Click on “Restore”.
- Close Apple Configurator once the iMac Pro reboots.
And that’s it. Your iMac Pro should now be booting up and working normally.