Samsung 840 Pro SSD is not recognized as internal drive

Clinton....

I agree with the problem of 'geniuses'. Much of the problem is that they are 'trained' by Apple and told what to think and how to analyse in the Apple way. They have caused me so many problems in the past with contradictory and wrong advice. It pays to try things and do your own research.

(I've just found out how to erase Time Machine back up files from an external hard drive, so I can do a full back up now).

But my main concern is that the SATA cable failed first, with the old HDD in place. With no warning!

Stephen,

That happens so frequently - the HD being recognized by the SATA cable or a USB device and the cables simply lacking the proper structure/specs to run an SSD - that we almost always jump to the "it's the cable" solution around here. You're not the first and you'll certainly not be the last!

Clinton

I had a similar problem and resolved it without replacing the cable. I bought a 512G Samsung 840 EVO SSD to upgrade my mid 2010 15" Macbook Pro. The Mac built-in recovery did not recognize the Samsung.

***First I re-opened the case to check the sata connection. It was plugged in fine but my MBP still wouldn't recognize the ssd.

***Next I decided to see whether or not I might have damaged the cable during install. So I plugged the old HD in and my machine booted fine. Cable was ok.

***So I decided to see if the disk itself was bad. So I plugged the Samsung into my Mac (using the old hard drive) with a SATA to USB adaptor... I got a message "Disk cannot be read. Do you want to initialize it?" I formatted the Samsung as "Mac OS Extended (Journaled)" using the Mac Disk Utility. The drive was not broken but was operating fine.

***So I reopened my mbp and plugged in the Samsung. This time...Success!

Some folks have surely had the cable issue. Nanortiz mentions running the Disk Utility (with samsung internal and old hd usb) and one user had a drive go bad that had been running well. But I stumbled on this thread looking for a solution to a very similar situation. I'm guessing some folks are having my problem too. I've installed countless HDs on windows and linux machines. It never occurred to me that the Mac built-in recovery could not recognize and format a new disk, whatever its format. I am very pleased with my fast new solid state drive :-)

Nanoritz,

Did you ever solve your problem? I am having the EXACT same problem with a newly installed Samsung Evo 840 1TB drive that I'm trying to make work in a mid-2010 Macbook Pro 17". I have tried a new SATA cable and that did not fix anything.

Here's another weird thing: when my new SSD is connected via SATA, the computer will not boot into OS X. But...when I boot into my Windows 7 bootcamp partition via SATA, everything works fine. smh...😕

whoinventedfreeride

Have you tried putting the SSD in an internal enclosure and booting from it? If it will boot from the enclosure, that puts the cable back on the table as a possible culprit (again).

Give it a shot and call bak,

Clinton

MacBook Pro (15” Late 2011), OS X Yosemite 10.10, 16GB Crucial RAM, 960GB M500 Crucial SSD, 27” Apple Thunderbolt Display

Clinton,

I am currently using the SSD from an external USB 2 enclosure. From the external enclosure, I can boot into OS X or Windows 7 (from a Bootcamp partition) just fine.

Last night I installed a new SATA cable with the hope that my problems would be solved. The new SSD would not boot OS X properly with the new SATA cable. I was, however, able to boot into Windows 7 with the SSD attached via both the old and new SATA cable. This leads me to believe that in fact the SATA cable is fine and there is something else that is preventing OS X from booting via the SATA cable.

Additionally, when I first installed the SSD, I was able to boot successfully into OS X about five times. Then I started getting the gray progress bar (underneath the apple icon) on startup, which eventually turned into a gray circle with a slash through it.

When I put back the old HDD into the machine, everything works fine via the SATA cable. To be specific, my 17" MPB is a mid-2010 model with an i7 chip. I am running Yosemite OS X 10.10.

Problem Solved: Turns out that my SATA cable was not bad. I am still using the original SATA cable (despite the fact that I ordered a new one).

Here's what solved my problem: Right after I installed the Samsung Evo 840 SSD, I used a third party app to enable TRIM. But apparently in Yosemite, apple will not allow the OS to boot if it detects that TRIM is enabled on a non-apple SSD.

I disabled TRIM and presto--my Samsung SSD boots just fine. What led me to investigate this solution is my Windows 7 bootcamp partition would always boot, even when OS X would not.

As a side note, I did notice for the first time that there is a gray progress bar that appears during startup. This initially worried me as a sign that something was wrong with the SSD. Apparently the gray progress bar during startup is a new, normal addition to Yosemite.

That's odd - after using the latest version of Trim Enabler and disabling the kext signing, I had trim enabled. I just re-installed Yosemite to get rid of the kext alteration - didn't have any problems booting with the kext scheme disabled.

Clinton

MacBook Pro (15” Late 2011), OS X Yosemite 10.10, 16GB Crucial RAM, 960GB M500 Crucial SSD, 27” Apple Thunderbolt Display

Good point. I did not think to disable Yosemite's kext signing. I guess right now I'm just happy that my new SSD is bootable!

Hi all,

I had the same history on troubles with Samsung SSD disk on SATA.
My configuration is Macbook Pro mid 2012 - Intel Core i7 2.9 Ghz - Now Yosemite 10.10 (at the 1st installation Mavericks 10.9.5) / Samsung SSD 840 EVO 1 TB

I installed the SSD and it worked flawlessy for 45 days. On 45th day, when I restarted the OSx , I got the grey folder icon with question mark.

I went to an Apple store where the guy was able to restart the system but adviced me to backup everything and have the SSD disk replaced by the vendor.

And so I did. In waiting for the new SSD I put in place my old 750 GB HDD.

Before the arrival of the SSD I upgraded the system to Yosemite.

When the new SSD arrived, I initialized it (Journaled HFS+) and carbon copy the HDD to SSD. The SSD was on a usb 3.0 tray. The process took more than 10 hours 😟

Ok, after the transfer I opened the Mac and swapped the disks.

Drum roll and....nothing!! Now, with the brand new SSD disk inside I have the same grey folder icon with question mark!!!

I googled everywhere to...well, you know.

So I was going to order a new cable, but was saturday morning (yesterday) so before committing the order I decided to check carefully which kind of cable was installed.

Accidentally I disconnetted the very small cable branch that connect to the I/F sensor.

So I reconnected it, and checked very carefully the connection.

Almost hopelessly, I restarted OSx.

Well, now it works!!!!

I don't know why, but it works.

In conclusion:

• the SSD drive is new but at the beginning it had the same problems of the 1st SSD;
• I just made a careful check of the I/F sensor connection

Nome processore: Intel Core i7

Velocità processore: 2,9 GHz

MacBookPro9,2

Nome processore: Intel Core i7

Velocità processore: 2,9 GHz

Nanortiz,

Have you resolved your problem? I am having the exact issue, but with both a Crucial X100 256gb and a Samsung 840 1tb SSD. Currently using a 3 year old Crucial 128gb SSD in a mid-2011 macbook pro with Yosemite and decided to upgrade to a bigger sad, thus the Crucial x100 256gb. Carbon copied new drive, booted up from external dock, but would not boot when put inside the Mac. Disk Utility shows that the drive has Partition Map Type: MBR (Master Boot Record); tried to reformat to a 1 partition with GUID, but process would hang at "waiting for disks to reappear"; also tried clean install Yosemite to the new drive on the dock, worked well and booted up the mac from the external drive, but would not boot when put inside, the same issue - Partition Map Type: MBR (Master Boot Record);

Don't think it's the sata cable issue as the old SSD still works when put back into the mac;

Similar situation with the Samsung 840.

No trim enabled in the mac.

Any help would be REALLY appreciated.

I'm having the same issues as you Manonedge, I was wondering if you have an update on your upgrade? I bout a Crucial M550 SSD 256GB and cannot partition it in the internal drive. I'm starting to think the hard drive cable needs to be replaced on my mid-2012 Macbook Pro?

This thread led me to research the KEXT Signing feature of Yosemite and this article explains that drawbacks of that approach so users can understand what the ramifications of choosing that option are. In my case I chose to disable the KEXT signing on my new SSD with trim enabled. Well then when I was done doing a few more things like updating dropbox, etc. I noticed I had a software update for yosemite for 10.10.2 or whatever. Since the SSD I was running was already on Yosemite I figured, "Sure it's just a small point update vs a major point update, so I'll just do this before I swap it over to my wife's mac book pro bay" Well, beware that, if you choose to enable TRIM on a third party SSD and disable the KEXT signing feature of Yosemite to do so, that the BOOT-ARG could be reset if the upgrade to Yosemite in the future happens to zap your PRAM. The same thing could happen if you zap your PRAM troubleshooting your previous issue because your designation of disabling the KEXT signing get's reset to ON instead of OFF like you set via SuperDuper or CarbonCopyCloner (super duper was WAY faster than CCC for what it's worth. SuperDuper took a couple hours and CarbonCopyCloner took nearly 2 days.)

Read these below as they helped me better understand why it worked one second and then why after an update it stopped working. I'm hoping that booting into recovery mode and re-setting the boot argument will allow me to boot back up.

http://blog.macsales.com/27116-disable-trim-before-upgrading-to-yosemite

http://blog.macsales.com/27116-disable-trim-before-upgrading-to-yosemite

~Tim

Hi

I'm having the exact same problem with my Samsung 850Pro SSD, 256 GB on a MBP medio 2012. I have used endless nights trying to figure out, what the problem is. I have finally ordered a new SATA cable, and I feel convinced that this will do the trick.

I also tried to boot the SSD from a USB3 interface, but until last night - no luck. But last night - success! I don't know if the solution below works for you, but try it out:

1. Press the on-button
2. When the process seems to get stuck, quickly disconnect the USB wire and put it back in
3. The Mac boots up like normal.

It seems that the SSD somehow looses connection while booting, and the way to correct this is to follow the steps above.

I can live with this, until the cable arrives. But its not a long term solution. Every time the computer goes into sleep mode, the USB looses connection, and I have to force restart... If anybody has any workarounds, you are more than well come.

Maybe I should note, that I'm running Mavericks right now to rule out any kext and trim problems.

Good luck :-)

Had the exact same problem, that you described. At first I couldn't believe that the problem is the HDD cable. After I read your post, I ordered a replacement cable from iFixit and now SSD is working again. Thanks.