Apple Event: May 7th at 7 am PT

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Samsung SSD 850 EVO doesn't show up in disk utility

Hello,

I have a macbook pro 2010 running OS X 10.6

I've just bought a Samsung SSD 850 EVO 250GB together with a SATA to usb adapter (nexstar).

I connected everything as requested, switched the adapter on but the disk doesn't show up in finder nor in disk utility.

Another external HD (USB) works fine, if this can help.

I've already read several discussions related to this problem without finding a solution.

Thanks.

Eugenio

MacBook Pro, Mac OS X (10.6.8)

Posted on Jun 26, 2015 5:59 AM

19 replies

Jun 30, 2015 1:01 PM in response to eugenio_from_here

Hi all,

I have finally borrowed for a few minutes a different sata-to-USB adapter, a very basic one, without external power (see the picture).

It works, at least I can see the drive in Disk Utility, so the problem was my adapter. I will return it but I am not sure if that exemplar was defective or if that model in general doesn't work well, so maybe I will change model. My question is: does it actually need external power source? As I said the one I've tried didn't have and it was well recognized, even if I didn't execute any operation.

Thanks

OGELTHORPE

Level 9

57,305 points

Jun 30, 2015 1:14 PM in response to eugenio_from_here

eugenio_from_here wrote:

My question is: does it actually need external power source? As I said the one I've tried didn't have and it was well recognized, even if I didn't execute any operation.

The MBP has sufficient power to run an external HDD/SSD so external power is not necessary. Try it again and see if you can format the SSD via Disk Utility>Erase to mac Os Extended (Journaled).

Ciao.

ricercar

Level 1

69 points

Aug 16, 2015 10:22 AM in response to eugenio_from_here

A similar problem appears with two Samsung EVO 850 SSDs that are not recognized by my NewerTech Voyager USB 3 SATA dock under MacOS X or Windows. The SSDs are recognized by a Western Digital USB2.0 external drive enclosure, but not the Voyager dock.

The NewerTech dock has an external power supply, but the WD drive enclosure does not.

I tried the solution of plugging the drives into the dock and powering up the dock before plugging the dock into my MacBook Pro, (June 2012) but this does not get the drives to appear in Mac OSX Yosemite (10.10.4) Finder, nor in Disk Utility 13 (606).

Suggestions welcome.

O2plus

Level 1

4 points

Nov 3, 2015 10:40 PM in response to eugenio_from_here

I just got my samsung 850 EVO 500GB and tried to follow the same procedure I used last year for my PNY SSD: plug it into one of my USB3 enclosures, format it with Disk Utility, then restore my system disk to it using CCC, before opening up my Mac-mini to install the new 850 as my system drive. Of course, this did not work: Disk Utility refused to format the 850 giving "error couldn't open device". What did work was to open up my hackintosh, unplug one of my sata disks, and plug the 850 directly into that free sata port. Disk Utility quickly formatted the 850 without complaint. Removed the formatted 850, plugged it back into my USB3 enclosure, and now CCC is happily cloning onto it! If I had simply installed the 850 directly in the Mac-mini and formatted/cloned it in situ, there would have been no trouble.

Samsung SSD 850 EVO doesn't show up in disk utility