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USB Drive doesn't show up in OSX?

M

MacNoobGuy

macrumors 6502
Original poster
Apr 18, 2012
497
0
hey guys, i've got a 4GB USB Drive here that i can't access. this is the error i keep getting: "The disk you inserted was not readable by this computer." i only have access to one machine so i can't try it on another PC.

i have very important work that i need to access. could someone please help me!

thanks

----------

ok i just tried running 'disk utility' and the USB drive in question shows up on the left hand side, but i'm not sure what to do as 'verify disk' isn't clickable.
 
In diskutility click the disk click erase click the drop down menu click os x case sensitive journaled title the drive erase the drive.
 
I don't think the OP wants to format the drive.... If the disk doesn't show up, at all and the system says that it's unrecognizable that is generally not very good.
 
pdjudd said:
I don't think the OP wants to format the drive.... If the disk doesn't show up, at all and the system says that it's unrecognizable that is generally not very good.
Click to expand...

well for some reason the USB Hub that the USB drive is connected to stopped working for 20 seconds or so... when i re-plugged the USB Drive back in i got this error... never had this error before. should i just wait until i can use a Windows laptop? what can i try to do in the mean time? what apps are there that could help me?

thanks!
 
Has it worked on your Mac before? Have you tried plugging it in again? Sometimes it can be finicky through a USB hub. Plug it directly into the computer?
 
First time that you told us about the hub - I second the suggestion to plug it directly into the mac since it sounds like your hub could be at fault.
 
ok thanks. can anyone recommend an app i can use to try to recover the data?

i really want to access the data on it!

i've tried rebooting the mac and re-plugging in the USB drive 100 times.
 
MacNoobGuy said:
ok thanks. can anyone recommend an app i can use to try to recover the data?

i really want to access the data on it!

i've tried rebooting the mac and re-plugging in the USB drive 100 times.
Click to expand...

I'd navigate to the drive in the Terminal, looking at the directory of the drive for hidden files and try and salvage stuff using the 'cp' command. You'll likely have to read up on what I'm talking about.

If not, go find a PC to plug it into.
 
ok i now have a Windows 7 laptop with me. what can i do on that to try to retrieve the files?
 
MacNoobGuy said:
ok i now have a Windows 7 laptop with me. what can i do on that to try to retrieve the files?
Click to expand...

It's not showing up on Windows? Not looking good.
Try looking at the drive through the Terminal (Applications>Utilities>Terminal.app). Here's a brief rundown of what I'd do:

Plug drive into Mac.
Open Terminal and type
Code: 
cd /
(the 'cd' command takes you to the '/' directory)
Type
Code: 
cd Volumes
Type
Code: 
ls
(this will list all items in the Volumes Directory, hopefully you see your drive in here)

If you don't see your drive and you're desperate for these files you'll need to start looking into file retrieving software.

If you do see your drive:
Then type
Code: 
cd (name of drive)
Now type
Code: 
ls -a
to list all items, including hidden items
Type
Code: 
mkdir ~/saved_drive
to make a new folder to save your stuff too on your Mac.
Type
Code: 
cp -a * ~/saved_drive
to try and copy everything in your thumb drive to a new folder "saved_drive" in your home folder on your Mac.
 
ok i just checked on the Mac App store and there are free apps available, but if you want to do any data recovery you have to buy the apps...

are there any free apps people could recommend?
thanks!
 
"are there any free apps people could recommend?"

There are no "free" data recovery apps that are user-friendly. They are ALL "pay for". They work like this:
1. You download the app for free
2. You run the app on the drive, it scans to see what it can find
3. If the app finds "recoverable data", it permits you to recover ONE file (and one only) as a "test"
4. If it looks like more files are recoverable, you then pay the fee, obtain a registration number, enter it, and the app "goes to work" on your problem drive.

Having written all of the above, there is STILL a reason why these programs might NOT be able to help you -- see below.

Just wondering -- do you have access to a PC that has Steve Gibson's "SpinRite" on it? I've never used it (I don't do Windows), but I've heard that it is the absolute BEST app there is, insofar as dealing with damaged drives is concerned.

Other thoughts:
Is the drive 4gb or 4 _terrabytes_?
How old is it?
Who made it?

A difficult problem when trying to access damaged USB drives that won't mount:

Even the best data recovery apps (Data Rescue 3 comes to mind) may not be of any use if the drive in question cannot be mounted on the desktop. I had this problem with a drive that had a damaged partition -- and the files on the damaged and un-mountable partition were those I wanted back.

But .... what to do next? No "drive repair" apps (notice that these are DIFFERENT THAN "data recovery" apps) could repair the drive to the point where the damaged partition was "mount-able".

My solution:
I RE-initialized the ENTIRE drive into a SINGLE partition (you are reading everything correctly). Yes, this destroyed all the existing partitions, and yes, it wiped out the drive's directory, as well.

BUT -- the data that was actually "out there" on the drive's sectors was left undamaged, because I chose NOT to "zero out" the drive, only to replace the damaged directories.

Once this was done, the drive was again "mountable" -- even though it showed on the desktop as an "empty" drive (no files at all) and ONE partition.

But -- because it was now mounted on the desktop, Data Rescue 3 could "see it". And DR3 was able to "do its magic" by by-passing the new directory and by going "right to the platters" to scavenge, and then re-construct, the data that it found out on the sectors of the drive.

The end result was I was able to get most of the files back. ALL previous folder hierarchies and most file names were lost (remember that file names and folders are constructs of the directory, which has been "wiped"), but the DATA itself was there.

As it happened, the files I was looking for were mp3's -- I dumped the whole batch (hundreds and hundreds) onto a drive that had a clean system (for this purpose) and into iTunes -- and iTunes was able to read the metadata that was still there, and in many cases re-assembled the mp3 files in their proper order.

The point of this whole story:

It -IS- possible to get the data back from a damaged USB drive that is no longer mountable.
BUT -- it takes work (MUCH work), time, the willingness to learn, and some MONEY.

You probably ain't gettin' there otherwise.

You will need
1. A SECOND external drive to serve as your scratch drive
2. Data Recovery software
3. Time
 
MacNoobGuy said:
ok thanks, but is there a data recovery App on OSX i can try before doing that?
Click to expand...

Why not do what I suggested? It takes 2 minutes, is free, and I wrote out exactly what you have to type. Or just buy one of the apps on the Mac store if your data is so important. How much are they?

What is on your thumb drive anyway that's so important?
 
GimmeSlack12 said:
It's not showing up on Windows? Not looking good.
Try looking at the drive through the Terminal (Applications>Utilities>Terminal.app). Here's a brief rundown of what I'd do:

Plug drive into Mac.
Open Terminal and type
Code: 
cd /
(the 'cd' command takes you to the '/' directory)
Type
Code: 
cd Volumes
Type
Code: 
ls
(this will list all items in the Volumes Directory, hopefully you see your drive in here)

If you don't see your drive and you're desperate for these files you'll need to start looking into file retrieving software.

If you do see your drive:
Then type
Code: 
cd (name of drive)
Now type
Code: 
ls -a
to list all items, including hidden items
Type
Code: 
mkdir ~/saved_drive
to make a new folder to save your stuff too on your Mac.
Type
Code: 
cp -a * ~/saved_drive
to try and copy everything in your thumb drive to a new folder "saved_drive" in your home folder on your Mac.
Click to expand...

ok i just tried this, but only the 'Macintosh HD' came up?
 
ok i just tried running spinrite and it ran a level 5 scan and i rebooted into Windows, but the drive was still unrecognisable to Windows so i formatted it using FAT32. i then ran 'HDTunePro' and it picked up two error blocks at the beginning of the scan, but no other error blocks were on the drive. i just tried running 'Recuva' but it gave this error: 'Failed to scan the following drives: E: Data Error (cyclic redundancy check'.

what can i do from here? any help would be really appreciated!
 
GimmeSlack12 said:
Umm, dude. You reformatted your USB drive? If you did that then the disk is erased :eek: .
Click to expand...

but i only used 'quick format' in Windows...

----------

is there anything else i can try and do? does anyone have experience with spinrite?
 
"but i only used 'quick format' in Windows..."

Doesn't matter -- looks like you're replaced the directory.
And the directory is the "pathway" to all files on the drive.

Looks like you may need some kind of data recovery software now, to get at the files, IF they are "still there".

Spinrite _might_ be able to get the data off. Perhaps it could be used to copy the drive's data sectors to a "known good drive", after which file recovery software might help there.

If you handed me this flashdrive to recover on my Mac, what I'd do is this:
1. Re-initialize it as HFS+
2. Use DataRescue3 to scavenge and recover any files it could find.

Possible problems:
I'm not sure whether DR3 could "see" and recover files on a drive that was previously in another format other than HFS+.

But I _can_ tell you that I have successfully recovered files (using DR3) from a corrupt (and previously multi-partitioned) drive by re-initializing it into ONE partition and then "attacking it" with DR3.
 
ok thanks, but how do i use spinrite? it completed it's 5 level scan, but i don't know what to do from here?

thanks!
 
I suggest.....

try Stellar Phoenix (Mac or Windows anyways). Maybe you will be able to recover the files. And strongly suggest you dont mess so much with a drive showing failures. Focus in get the info, if have a value for you....:(

:):apple:
 
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