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NigelGordon

macrumors newbie
Original poster
Oct 28, 2017
5
0
Leicester UK
I was in the process of erasing the HD on my old IMac (late 2008) prior to giving it away to a good cause. Was doing the highest level of erase as there had been some sensitive material on the system. On pass 4 of the erase there was a power failure. When I restarted the IMac the and tried to restart the erase I got an message that the disk could not be unmounted. Looking at the disk list in disk utility the disk has no name. Have tried all the tricks I know but can't find a way to make the disk mountable, so that erase can unmount it and rename it. Any ideas?
 
No, do not have the information on how to do this. My understanding is that I would need the device name and at the moment it does not have a name.
 
So when you boot up on the OS disks you are saying it won't let you select the internal drive or it doesn't show up in disk utility running from the install disks? Correct? If it won't show up at all then I would dare say your drive is crashed.
[doublepost=1509234051][/doublepost]Read this post it looks to be similar problem as yours.

https://forums.macrumors.com/thread...-reset-my-imac-to-factory-conditions.1687224/
 
Have found a solution. You go into recovery mode (Cmd-R during boot) and then select disk utilities. Once in disk utilities select the physical device which has the unnamed disk on it. The run First Aid on the device. The effect of running First Aid is that First Aid mounts the device. You can then run Erase and reset the device name in the Erase options.

WARNING - You must do the Erase immediately after First Aid has finished. If you don't the system will unmount the drive and Erase will not be able to unmount it to operate.
 
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