Not recognising USB HDD after deleting data.

[Jonzjob]

MBP 13 running El Capitan

I been looking at one of my external HDDs and decided that the stuff on it was not needed any more, so I did a select all and 'Move to trash'. Then I wanted to change it from Fat32 to Mac OS Extended (Journalled). I opened Disk Utilities and there was no external HDD shown, so I checked it on Finder. Nothing there either and when I looked at the disk the blue light on the case was flashing very fast. I disconnect/reconnected it and it was the same. I did a restart with it connected and it still didn't show.

I then tried it on our iMac, running Yosemite, and it was exactly the same. So it looks as if something is screwed on the HDD?

Any ideas please? I suppose tha I could try it in a different caddy?

 

[ferrarr]

Can you start up into Recovery mode, go in to Disk Utility and see if it shows there?

Trying it on different machines, could mean the drive has died.

 

[Jonzjob]

It doesn't show on either of our machines, so I am with you in that the dammed thing has died!! It's the first one that I have die at home. I have seen many die on other peoples IBM mainframes over the 18 years I was with them, but this is my first and I'm very gald I don't have anything that isn't backed up. Backed up a couple of times for most of it!

Oh well, as the French say "say-la veee" Not the way they spell it but as I have difficulty spelling in English my French has NO chance :Blushing::Blushing::Blushing:

Edit : - I have just tried it in another caddie. Then I found that it still didn't shop in Finder, but when I tried it in Disk Utilities I found that it stopped Disk Utilities showing anything. It just has the spinning wheel showing that it's trying to see what's there? I then disconnected the HD and Disk Utility showed the 2 internal HDs OK. So I think that's a definate dead disk!

Never mind, it gives me another lovely ball breaing race and another VERY powerful magnet

 

[Rod]

Just one question from me; after you trashed the "All contents" in the first instance did you empty the trash before ejecting the USB drive. I assume you did eject it, rather than just unplugging it? The reason I mention that is because if you are in the process of removing a large amount of data and try to eject, you will get a message saying it is in use. Interrupting that process is likely to corrupt the whole drive.


Sent from my iPhone using Mac Forums

 

[Jonzjob]

As far as I can remember I then went to Disk Utilities to Partition it ready for Carbon Copy Cloner and I remember thinking that the trashing was a pointless step. I didn't try to disconnect it at all.

I think that it's lost the sector zero on the disk and that would make it knackered!

 

[harryb2448]

I am with Rod. I think the drive has been killed stone dead. Critical emptying Trash whilst connected and letting it run until it finishes. It was a pointless step if you simply used Disk Utility to Erase and Format rather than using Move All to Trash.

Perhaps leaving it stand for a few days and reconnecting may help. Utilities like DiskWarrior and Tech Too Pro may save it, but at a hundred bucks simpler and cheaper to replace.

 

[Jonzjob]

I realised the pointless step too late Harry, but I'll try not to forget it. It's a 750gig disk and as you say it ain't tooooo expensive to replace.

It ain't going to cost owt to leave it a few days either, so I'll try that. Nowt to loose is there.

Off track a bit, but I hope you aren't too close to those fires mate!! I know they are inland a fair way from you, but?? You can have some of our rain if you want!!

 

[harryb2448]

No thanks mate I am on the Mid North Coast of NSW right on the ocean and river. Most fires here some more inland at the moment, particularly the Hunter Valley.

 

[Jonzjob]

A few daze later and I definatly have a dead HD, but not all is lost because I will strip it out. The head magnet is something to behold and I will have a use for the actual disk main bearing. Nowt goes to waste here..

Just as a matter of interest. One of the early disk units I used to work on when I was employed by IBM, the heads were drived by hydraulics! Yes, that's the oily stuff and everything, including the heads was usually oily! Oil drived and mechanical indent to lock the heads on track. They weren't as fast as todays disks. I wonder why ? The access time was under 200 ms!

 

[chscag]

Just as a matter of interest. One of the early disk units I used to work on when I was employed by IBM, the heads were drived by hydraulics!

Hey John, remember the pneumatic tape drives used by the 360-50 mainframes? Lots of fun when one of doors would come open and tape started flying all over the computer room. Those were fun days working in 62 degrees F computer rooms!

 

[Jonzjob]

3420s. The first time I ever used super glue was to do a repair on the head of one of those. It took me about 20 minutes to get my finger off the dammed thing!!! Apart from that, they were really good machines to work on and the vac columns were a treat to set up. Your guys weren't doing it right if the tape was flying!!

 

[Jonzjob]

Well, I have had a closer look at it but it still doesn't work



I even washed me hands before I took the platters out