External hard drive not showing its full capacity

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Level 1

5 points

External hard drive not showing its full capacity

Hi

I had a Toshiba canvio 3TB hard drive connected to my imac permanently(not used as Time machine back up at the time although it did have backups from when it WAS used)) and noticed today that it wasn't showing up at all.To cut a long story short it turns out the "caddy" which it was in wasn't working so after much difficulty I managed to remove it from the case.I put it into an external hard drive reader and it shows up in my finder but NOW I only have 801GB of storage on this 3TB hard drive.

I plugged the hard drive reader into a windows pc and again it only shows 801GB.

Is there a way to get this back?The part of the hard drive that IS available works perfectly ok so I'm guessing the hard drive isn't corrupt.

Please help

iMac, OS X Mountain Lion (10.8.3)

Posted on Oct 10, 2013 1:12 PM

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Answer 1

rkaufmann87

Level 10

140,808 points

Oct 10, 2013 1:44 PM in response to petersiva

It appears to be partitioned into 2 partitions, why not remove one partition and re-format.

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Answer 2

BDAqua

Level 10

239,447 points

Oct 10, 2013 1:49 PM in response to petersiva

That sounds like your new caddy's chipset doesn't handle the new Advanced Format, that'll cause big problems... don't write anything to it until you get another caddy.

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Answer 3

petersiva Author

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5 points

Oct 10, 2013 1:59 PM in response to rkaufmann87

Thanks for the reply.

I actually "erased" the hard drive within disk utilty with the "801.57 GB TOSHIBA DT01" highlighted but I just still end up with those same 2 partitions underneath.One 207.7MB and the other 801 GB but still missing 2TB

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Answer 4

petersiva Author

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5 points

Oct 10, 2013 2:04 PM in response to BDAqua

Hi

I've got one of these

The toshiba canvio HD was working fine for nearly a year until today.I took it out of the caddy and stuck it in this usb reader but all I got was a partition of 850 GB

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Answer 5

rkaufmann87

Level 10

140,808 points

Oct 10, 2013 2:09 PM in response to petersiva

I see, I'd recommend instead of using a caddy using a proper enclosure. OWC (www.macsales.com) makes some very nice FW 400 & 800 enclosures.

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Answer 6

petersiva Author

Level 1

5 points

Oct 10, 2013 2:30 PM in response to rkaufmann87

I intend to get a decent caddy as soon as I can find out where my other 2TBs has gone.i actually put a different HD into the toshiba caddy and that didn't work either so the connections on the toshiba are faulty.

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Answer 7

BDAqua

Level 10

239,447 points

Oct 10, 2013 4:11 PM in response to petersiva

Did an Advanced format drive ever work in the Toshiba caddy?

New Drives have 4096 Byte Sectores instead of the old 512 Bite Sectors, & older caddies/enclosures do not understand the new Format. Some even have drive size limits, lower than the 2.1 TB of 512 Byte limit.

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Answer 8

petersiva Author

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5 points

Oct 10, 2013 11:41 PM in response to BDAqua

Sorry I don't understand what u mean.I'm not that technically minded I'm afraid.All I can tell you is that the toshiba caddy which had the original hd in doesn't work.I even put another drive in it which I KNOW works and that didn't read it either.

The issue I have now is I can't understand where 2TB of storage has disappeared to

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Answer 9

Seadee

Level 1

4 points

Nov 22, 2013 3:45 PM in response to petersiva

Hi there:

I'm helping a friend who just experienced the exact same thing as you, petersiva: Had the 3TB external Toshiba permanently attached to his iMac for over a year with no issues, then one day it wouldn't show up.

Today we pried apart the Toshiba case (not easy!), took out the drive, dropped it in a similar device to the one you have, and it showed up, but asked to initialise, which we did not do, of course. Attached it to Mac and Windows computers and it shows up as a 801GB and 746GB (blank) partitions on both. And of course, there are pictures he wants that are no where else.

Did you ever get a resolution to this? A partial run of TestDisk shows bad paritions and PhotoRec wasn't able or would not recover any files, wouldn't even acknowledge any sub-files after identifying only the 801GB/746GB drives.

Ubuntu wouldn't even see the drive.

Just curious if/how you resolved this and if you have any pearls of wisdom. Help!

Thanks for reading.

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Answer 10

petersiva Author

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5 points

Nov 22, 2013 3:54 PM in response to Seadee

Hi

I didn't get anywhere with it unfortunately but on the off chance I emailed amazon and they said to return it for a full refund even though I had it for 6 months and had opened it up.I actually bought a different drive to use for my back up as I don't trust these canvio drives.

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Answer 11

Seadee

Level 1

4 points

Nov 22, 2013 4:17 PM in response to petersiva

Wow, thanks for the quick reply. Too bad you couldn't get your info off of it.

I think I just came up with why we're getting the 801GB/746GB instead of the 3TB using the SATA to USB adapter. I just assumed it would handle ALL larger drives. Not so, website says it can handle UP TO 2TB drives.

Thankfully I bought a real external drive enclosure that says it's good for drives up to 4TB, so back to his house to try that.

Thanks for the feedback. I really appreciate it.

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Answer 12

Seadee

Level 1

4 points

Nov 22, 2013 4:44 PM in response to Seadee

To be clear, my SATA to USB adapter (operates like yours) has a 2TB limit; I'm thinking yours may have had the same.

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Answer 13

Seadee

Level 1

4 points

Nov 24, 2013 12:55 PM in response to Seadee

As I suspected above, it was the USB to SATA adapter I was using that had a drive-size limit. My adapter (a Kingwin Model #EZD-2535) has a 2TB limit (which I didn't no since it's no where on the box, only on the website, so the drive was see as 800GB/746GB, not the full 3TB.

Bought an external case (that you have to screw the drive into) that is capable of 3TB and above (Purex U3PD/S from MicroCenter, but you can probably get it online).

Plugged it into a computer running Ubuntu from CD and voila! was able to see the full 3TB and all the files.

So check the drive-size capabilities of your replacement external cases or USB to SATA converters. Would have saved me a few hours. Hope this does for you.

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Answer 14

Seadee

Level 1

4 points

Nov 27, 2013 11:58 AM in response to Seadee

Spelling police: "which I didn't know* (not no) 😊

Also, to be clear, I ran Ubuntu because I didn't have access to a Mac at the time and I was anxious to see if the full 3TB could be accessed. So in this case, the Toshiba Canvio case was at fault, the drive itself was fine and could later be accessed by Mac without further work.

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