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rib00

macrumors newbie
Original poster
MacBook Air 2017
Mac OS Monterey

I connected an HDD to my MacBook Air using a Sata to USB 2.0 cable. The HDD had a bootable Windows 10 or Windows 7 install on it. The drive had sat for a looong time without power (maybe 3 years).

The 2 partitions for this HDD were visible on my desktop. The first partition was a 500 MB EFI or maybe MBR partition. The rest of the drive is a single partition, probably NTFS. (As an aside, I viewed the top level folders on the NTFS drive-- maybe 7 or so folders, I think that 2 were program file folders.)

I opened Disk Utility and I selected the larger partition and I chose "erase."

I chose to format the drive as HFS+ (OSX Extended Journaled).

There are options of how securely you what to erase what is already on the disk, I chose 1 level up from the weakest. This means that Disk Utility will overwrite what is on the disk 2 times.

Then I let it start the process. I immediately got this error

Disk Utility Couldn't open disk -69879

Next, I tried the same thing on the 500MB partition. Same result.

Now, neither of the partitions show in disk utility (or on the desktop).
 
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Did you unmount all the partitions first?

Use diskutil list to list all the partitions of all the disk.

Use mount to see if any of the partitions are mounted.

Use diskutil unmount disk#s# to unmount a partition.
Use diskutil unmount disk# to unmount a disk.
 
Did you unmount all the partitions first?
No, I did not do that. I don't know how to try again using your method.
Follow the Apple's instructions to erase the whole drive, not partitions one by one
Erase and reformat a storage device in Disk Utility on Mac https://support.apple.com/guide/dis...at-a-storage-device-dskutl14079/21.0/mac/12.0
Thank you. I did want to do that originally but I didn't see how to do that.

However, the drive is NOT consistently showing as connected to my computer.
The disk stopped showing in Finder (left hand side) after the error happened.
I rebooted and the drive did not show on the desktop or in Disk Utility. This all happened yesterday.
I booted up the computer today and 1 partition labeled "Windows" showed on the desktop. I think that is the name for the larger of the 2 partitions. Once I opened Disk Utility, that partition disappeared. I went to view -> show discs and still the disk did not show. Also around the time that I opened disk utility I heard the hard drive spin down and then start spinning again and this repeated.
 
Do you have another computer, particularly Windows, that you could plug the drive in and see if you can do anything with it? It's possible the drive itself is failing or has failed. If it's an SSD it may be stuck in read-only mode.
 
Do you have another computer, particularly Windows, that you could plug the drive in and see if you can do anything with it?
I'd rather not as the drive ranks a little lower in trust than just about all other hardware that I use. This is because the drive was purchased second hand. The specific concern is malware. (I bought the computer that the drive came out of refurbished, then removed the drive soon after and used the computer with my own drive installed.)

I really don't think my Linux machine would have a problem with the drive. I'd actually put money on the Linux machine being able to repair whatever the mess is. Here is supporting evidence (this is another thread of mine concerning a similar experience to this thread's OP):
Quote from the OP:
2) I have the disc inserted on a Linux Machine running GParted. All geared up to fix this mess.
(the software is ready to fix it, just need to make the user selections in the software.)
 
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I unplugged from current USB port
I plugged into other USB port
The large Windows partition icon showed on the desktop
I opened it
I then opened "program files" or "program files x86" (can't remember)
The file manager immediately closed and the the large Windows partition disappeared on the desktop
A few seconds later, the desktop icon for Windows partition reappeared

Edit:
I just tried to erase the drive (the whole drive, not just one partition).
That failed with the same error code.
Maybe I still had the one or both partitions mounted at the time that I did that. I forgot to check. I think that there were actually 3 partitions showing in Disk Utility right before I tried to erase. Maybe one was (partially) created in the failed attempt described in the OP?
 
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Is it a bus-powered drive, or does it have its own AC power adapter?

It could be pulling too much power, or trying to.
tldr - I think power source is theoretically* clean.
The drive is connected to a power adapter, which is plugged into the wall.
The power adapter came with the USB 2.0 to sata adapter. And actually, it's not just a sata adapter. I think the adapter can also handle IDE. Maybe Scsi, too. (I can research.)

If you still think it could be a power issue, I can try a different power source. But, would be a bit of a headache for me to implement.

--
*the wall receptacle could be a little "dirty" (not running off a quality battery). Spike and surge protector is pointless b/c the receptacle is not grounded.
--
the computer has been sitting, with the drive powered up and connected for 3+ hours.
it has approx 8 instances of "the disk you attached was not readable by this computer."
 
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If you don't need any of the data on it, try zeroing out the partition table etc. to make it all "fresh".

Use diskutil list to get the ID of the disk (eg. disk2), then use sudo dd if=/dev/zero of=/dev/rdisk2 bs=1m to start writing zeroes to the disk (note the use of rdisk rather than disk, and make sure you have the correct disk number!).

Since you only need to wipe the start of the disk, you can abort with Ctrl-C after a few seconds. Hopefully Disk Utility will then prompt you to format the disk.
 
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If you don't need any of the data on it, try zeroing out the partition table etc. to make it all "fresh".

Use diskutil list to get the ID of the disk (eg. disk2),
I am in disk recovery (I booted to this to try something else). So, figured I would try your suggestion there.
running Bash 3.2.
lol - there are 21 disks
Didn't try the second command here.

Edit:
Now I am back in the graphical user interface of Monterey
notable result of first command
Disk 2, which is the external disk, has a partition of type 0x27.

running the 2nd command exactly as you typed it in your post, I think I got an error. I did not have to press control C to exit it because it was so fast (see below). Yes, the problematic external drive is disk 2. As an aside, the GUI warned me that Terminal was going to do something to an external disk and I had to say ok. So, it was the right disk.
dd: /dev/rdisk2: device not configured
3+0 records in
2+0 records out
~ 2 million bytes transferred in ~ 0.15 seconds

I never knew about /dev/zero. very cool to know.

Edit 2:
Now disk 2 has
partition 0, no name, no type.
So, maybe the second command worked as intended.

I do see the drive in disk utility. Erase, First Aid, and restore are all available options. Should I try erase?
Before doing that, do I need to make sure it's NOT mounted?
 
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I do see the drive in disk utility. Erase, First Aid, and restore are all available options. Should I try erase?
Before doing that, do I need to make sure it's NOT mounted?
In Disk Utility, select View menu > Show All Devices. Select the top most icon in tree representing your ext drive. Click "Erase".
 
In Disk Utility, select View menu > Show All Devices. Select the top most icon in tree representing your ext drive. Click "Erase".
Thank you.
But, unfortunately, mostly back to square one. Disk Utility says

unmounting disk
creating the partition map
couldn't open device. : (-69877)
Operation failed
 
There are now 2 drives that are bricked basically as far as this version of Mac OS is concerned. Here is the other one.
And these are the only 2 devices that I have performed a disk operation on using Disk Utility on this machine.
I think it's so unlikely that these 2 drives were just at end of life. I mean come on! 0 for 2?!

Here is some history on each device:
the 2017 MacBook Air - just bought it, ran about 13 passes on the Ram with Memtest86+ and I ran Apple's hardware check. When I got it, it's running Monterey which is way past end of life for security updates from Apple. I didn't get the sense that the seller is at all a power user based on my interactions with him.

Thumb drive: probably 7-8 years old. Not used much over those years.

Hard drive: Right before the OP, I did put the drive into the windows machine that it came out of. Windows said no boot drive. But, that did not alarm me at all because 1) the drive had sat for a long time, prob 3+ years. So, bit rot is possible; 2) maybe the motherboard firmware was set to only boot to one specific sata connection; 3) could be a loose cable; 4) it's possible that I updated the motherboard firmware while that drive was removed. Not sure if that alone could cause the message at boot.
The drive is a pain to get in and out of the computer so I just decided to not troubleshoot it. My reason for booting to Windows was very minor and I almost didn't bother. All that being said, I still had 99% belief that the drive was fine.

If I buy a brand new 3rd drive (prob a USB thumb drive), and that has similar experience, what would you all want to start pointing to as the culprit? I really don't feel like wrecking another data drive (with the price of drives these days) but I might have to to put the "nail in the coffin."
 
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