Hard drive will not mount shows up in Disk Utility

Thank you for the suggestions.

I tried using Terminal to mount and unmount.

The drive appears in Disk Utility but is faded like a connected but unmounted drive.

Unmount: it replies "disk1s2 was already not mounted unknownc8bcc8ed76ed:~ (my main drive name)"

Mount: It replies "Volume on disk1s2 failed to mount unknownc8bcc8ed76ed:~ (my main drive name)"

Last night I used Drive Genius to duplicate the drive as a backup. (I do not have a backup of this drive pre-problem). I had an identical drive available. The result is that both drives look and act exactly the same. I was hoping I could access the content and just reformat the original drive.

So it is not the hardware enclosure or Firewire (interface, ports, cables, etc.) as other FW devices work properly and the 2nd drive worked before the files were duplicated to it.

I waited until the evening to attempt Restore in Disk Utility so it could run all night. You drag the source to the field from the list of connected drives in the left column. The drive and the partitioned volume show up. The drive name is bright and clear but the volume is faded like an unmounted drive hooked up and running.** I tried dragging both individually but they did not drop in the field. I tested the procedure by dragging the current working boot drive to the source field. A + plus symbol appeared as I dragged the name over the field and the volume name populated the field when I released the mouse button. So Restore in Disk Utility is not possible when the hard drive is unmounted

**In case the question comes to mind, I have attempted to mount the drive and the volume individually without success.

Regarding my statement that you quoted (I don't see a Quote option here) I think it at least greatly increases the odds that this is the situation when the duplicated drive behaves the same way, as much as can be observed, when it was healthy before.

Regarding Restore and unmounted drives, I plugged in a separate external hard drive and allowed it to mount. I used Disk Utility to unmount the drive. I attempted to use Restore but it would not allow the drive to be used as a source once it was unmounted. Are you able to use an unmounted hard drive as a Restore source on your system?

Regarding the warranty, these were all empty cases and raw hard drives that I assembled so I am free to swap them around. It is just a last resort because the process is tedious and although I am careful each time you disassemble and reassemble things it takes a toll on the hardware. Especially with all that is involved in the layers of steps swapping the internal drive of a Mac Mini they are not meant to withstand the process indefinitely.

I will try swapping external drives with casings before swapping with the internal and doing an Archive and Install of the OS.

Quoting is done via the speech bubble

Thanks I see the bubble.

I am using Snow Leopard 10.6.8. The link is information pertaining to Lion 10.7 and above so maybe things changed. I did not see anything that would allow me to work with an unmounted drive in my Disk Utility.

I followed the instructions on the linked page and enabled Debug mode. I turned on a different external drive and allowed it to mount. Then I unmounted this drive. Once unmounted I could not use it as a source. I could use it as a destination though. Not aware of this earlier I tried the same steps with the problem drive. Although it cannot be mounted and it cannot be used as a source it can be used as a destination. Strange to me but what do I know?

I am going to try swapping out external drive cases.

I took the problematic hard drive and installed it in my Mac Mini so I could attempt a Safe Boot and then Archive and Install if necessary.

Safe Mode didn't work. The drive produced the circle with a slash symbol.

I reset the PRAM which was part of a list of steps to work through I found created by Apple Support.

I was able to boot up to Verbose Mode and view the text of the boot process. I wrote it all down. I can answer questions about the content better than typing it all out exactly. It includes, "...journal magic is bad..." "...failed to open..." and ends with "...cannot mount root, errno = 19"

I attempted Archive and Install however when it went to show what target drives were available it was a blank box and all buttons were grayed out.

I rebooted and opened Disk Utility from the DVD. The drive appeared the same with the top main line bright and the partitioned volume faded. Still was unable to mount. I ran Verify and this time a red line of text appeared "Invalid content in Journal" and at the end I ran Repair. When running I could read line by line and at one point it showed "checking volume information" then the following line "Repairing volume" the following line "Rechecking volume" more line of checking then it ended with "The volume was repaired successfully."

It still would not mount. I ran Verify again and again said "Invalid content in Journal" and this time it stopped midway saying "The volume was found corrupt and needs to be repaired. Error: This disk needs to be repaired. Click Repair Disk."

I clicked Repair and it ended with The vol. was repaired successfully."

Still unable to mount I began repeating Repair over and over. Each time it found something to repair and ended with a success message. After several more Repairs I tried Verify and it stopped midway saying to Repair the disk.

Question: Does running Repair multiple times continue to correct bits and pieces little by little or is this a generic message and we should treat it as a problem Disk Utility cannot pinpoint and is just beating its head against the wall?

The step by step instructions I downloaded mentioned running Repair more than once but it did not say that running it 20 times would erode some problems and eventually lead to a fully repaired disk (if the problem was something DU could take care of in the first place). At this point I have run Repair about 20 times total with a series of 10 back to back skipping Verify. I keep seeing the lines about invalid content in a journal and that it repaired something successfully. Yet I still cannot mount the disk.

Drew Reece wrote:

The error logs you post are too vague…

"...journal magic is bad..." "...failed to open..." and ends with "...cannot mount root, errno = 19"

That is worthless, photograph, screenshot or copy & paste the full text if you want us to help, tiny fragments tell is very little at all.

I cannot use any functions that would screen capture or copy so I could paste it here. I cannot photograph it because it constantly streams as it tries to boot up and it would be blur. The motion is too fast and the text too small to use the camera and produce a sharp image of text that can be read. I was hoping someone might ask if there was something specific present in the information. I said I could answer questions better than type it all out. I quoted those bits as a start not with the intent of picking what I thought was important.

As I described earlier I duplicated this drive and the target behaves the same way now. If the drive is behaving this way because it is physically damaged how could that be transferred to another drive by duplicating its data? That would rule out physical damage although that could also be present and the second drive could suddenly share the same physical damage in an almost impossibly rare coincidence. Neither produce sounds other than the gentle hum they have always made.

At the least I need some data off the disk. It was originally the internal drive to one of my computers. I was keeping it in tact until I was done using it as a model to pattern the new drive after. I continued to use it as an option, booting to it and the new drive depending on the need. If I could access the content I would just pull off what I needed and reformat the drive.

If a healthy drive is performing an operation rather than sitting idle when there is an interruption in power can this produce physical damage that would show these symptoms? I don't know if it was active. I just don't know that it was not active at that moment.

This is 10.6.8 so I found a copy of Data Recovery 3.0 which should be here Weds.

Does running this type of software on a drive only to look around create any of the potential damage or decrease the ability to retrieve data?

Or does that only come into play when you command the software to begin attempting to retrieve data?