New SSD will not boot internally, only from USB.

If it works externally and not internally, it's the SATA cable.

I had the same problem, but I swapped the drives before cloning using Disk Utility on my second try. My original HDD was plugged in through USB with the new SSD installed internally. That worked like a charm. You will probably need to hold down the Option key on the first startup following the cloning though and select the SSD. After that, it boots automatically to the SSD. I hope this helps everyone else.

But if the problem is the SATA cable why would my Apple HDD work fine when connected internally? It's only the SSD that doesn't work internally.

Because the SSD is a lot more demanding on the cable than an HD. It's carrying a lot more data than the HD, so a marginal cable is going to cause problems. Search these forums, this happens all the time and a new cable resolves the problem. It makes no sense that it would be a Crucial problem. You've already proven the drive works.

I'll give it a shot.

Just because the drive boots externally doesn't necessarily exclude crucial from my error elimination list.

I used Carbon Copy today when I cloned by Crucial Drive. It booted fine on my external in closed drive. However, tonight I have the flashing folder.

Based on what I read I would think the cable needs to be replaced?

Sounds like it, yes.

I fixit has a used one for $50. I found the same one on Amazon for $30 new. Why shouldn't I buy the new one?

You should. Ifixit doesn't always have the best prices, but it's a great place to find the part numbers. If you're sure it's the same part, but it from Amazon.

Yes. I just ordered it from powerbookmedic.com and it was the same part number and OEM Apple. It was $29 plus shipping. I will install it Friday and report back.

So here is an update on my situation...

I received the cable from PowerBook Medic.com. I replaced the cable however after calling about another issue they said the cable was incorrect for my unibody. I have an Early 09 15" MBP. They are sending me a new one. There customer service is fantastic.

Note to those attempting to do this themself. iFixIt.com does not mention that when removing the right speaker wire that it is soldered to the board! They made it seem as if it was sticking by ashesive. So now I may need to replace my logic board! 😟

I put my old HD back in, despite the wrong Sata Cable, booted fine. The Crucial SSD won't boot. Tomorrow I plan on doing another clone and dropping it in. I hope that works; this is rather frustrating!

Here is more of an update. I hope someone can help me because I am very frustrated.

1) I erased the drive and re-cloned it with no issues.

2) The drive does show when I go to boot from it. I think I booted into the drive. It was asking me for my DropBox login information. Is there any other way for me to know if I booted into the drive? I only HD was still showing on my desktop.

3) When I go to reinstall the new SDD I still have the question mark folder appearing. The SATA cable has been replaced. Could it be the drive is bad??

HELP!!!

I'm really not sure where you're at right now. Was the SSD clone created when the new SATA cable was in place?

Yes, it was.

This morning, after doing further research, I decided to swap the drives. Meaning put my old HDD in the external and install the SSD inside the machine. I held down command R and wiped the drive clean. I am now in the process of installing the OS X.

I hope this works. This was a solution that worked for many people.

Similar problem. Late 2011 MBP, Crucial M500 240Gb SSD, cloned fine with Carbon Copy over usb. After install, it could not be seen. Reinstalled HDD, SSD now cannot be seen over USB. Returning to Amazon. At least they make the return easy.