Question My iMac is running OS X Mavericks. I have a Samsung 480 GB SSD (commercial) that is formatted Guid and installed in a USB 3.0

[rickmac]

SSD in external powered USB enclosure is not recognized by OS X.

 

[SaZDice]

you need to place it in SATA port not usb

 

[SuperSoph_WD]

Hey there, rickmac!

Have you tried the SSD in the external enclosure on another computer?
I'd try it with a different cable as well, even though it's USB 3.0. It's possible that the cable doesn't provide enough power for the SSD in an enclosure.
I think that the problem can be also in the enclosure itself and the SATA to USB bridge controller inside.
Supposedly, the SATA would be much faster than USB 3.0 as @SaZDice suggested.
Finally, I'd simply change the enclosure and see if it would help the Mac to recognize the external SSD.

Hope this helped!
SuperSoph_WD

 

[Ijack]

When you say "not recognized" do you mean that it doesn't appear in Disk Utility? Presumably your iMac is new enough to support USB 3.0.

 

[rickmac]

I have tried the SSD in an unpowered enclosure with the same results - Disk Utility doesn't see it. As I write this I have a different SSD (OCZ Vertex Plus R2) in that same unpowered enclose and Disk Utility see it. I just removed the OCZ SSD and plugged in a Seagate 2-1/2-inch Hybrid SSD in and Disk utility sees sit, too. I just REFUSES to see the Samsung SSD. I've used the powered enclosure on Win 7 and Linux and it works fine there. I'm still stumped, because the Samsung SSD works on both Linux AND Win 7!!!! Just won't work on my iMac (Late 2013) 27 inch, 14,2

 

[rickmac]

exFat didn't work. No matter how I format the drive, OS X Mavericks 10.9.5 simply doesn't see it when I use USB. I haven't tried it as SATA, because I have to open the iMac and I don't want to void the warranty. I am using SATA to USB adapter that works with EVERY other HDD or SSD I plug in to it. I just formatted the SSD in Linux as HFS and still my iMac won't recognize it! Arrgh! This is frustrating. It is obvious that the drive is not bad because it works in both Linux and Windows 7.

I wonder if I need a firmware update on the Samsung drive? If I do, then I'm probably dead in the water, because Samsung doesn't even list this drive's model number, MZ-7PD4800/0D3.

And to answer Ijack, my iMac has only USB 3 ports, which I use when I plug in the SSD.

 

[SaZDice]

did you try reformatting it on a windows pc using transmac(running it as admin) , then put it?

 

[Paul NZ]

One site says this ssd is a 840 pro with specialized firmware that’s optimized for mainstream, ready-heavy data center applications and more over-provisioning of the NAND

 

[SuperSoph_WD]

Hi again, rickmac!

I'd plug the SSD to a Windows PC with the external enclosure
Then initialize the drive as GPT (GUID Partition Table) with the disk management
After being formatting, I suggest to safely remove it and plug it in the iMac.
Then you will need to initialize and format it again, but it should work.

Hope this helps. Good luck!
SuperSoph_WD

 

[rickmac]

did you try reformatting it on a windows pc using transmac(running it as admin) , then put it?

 

[rickmac]

Did that - didn't work. Finally got someone from Samsung on the phone andfound out the SSD I bought is obsolete and will NOT run on OS X. Problem solved. The SSD now is running my Win 7 PC and humming merrrily along. Go figure!

 

[SuperSoph_WD]

Did that - didn't work. Finally got someone from Samsung on the phone andfound out the SSD I bought is obsolete and will NOT run on OS X. Problem solved. The SSD now is running my Win 7 PC and humming merrrily along. Go figure!

This is truly the first time I come across such a problem.
Well, at least you solved you issue, though!

Happy computing!
SuperSoph_WD