EXTERNAL BOOT DRIVE MAC NOT BOOT INSTALL
EXTERNAL BOOT DRIVE MAC NOT BOOT PRO

I formatted the disk (Mac OS Journaled, GUID partition table), downloaded El Captain (newest version that supports that model MBP), and installed it on the internal drive. From there the OS could see the internal SSD drive I had installed. To my surprise it was detected by the OS when doing an 'Option' boot and I was able to load OS X. As one last ditch effort, I tried plugging in the old thought-to-be-damaged hard drive into into an external USB SATA dock. (In between these steps I did countless SMC and NVRAM resets, checked connections, did the tape trick, blew off dust, etc)ДЄt this point I assumed I had a broken hard drive cable.

Plugged in new SSD, tried booting while holding Option, drive was not detected.

Purchased new SSD thinking it was a damaged drive (it was not).

Opened it up, disconnected and reconnected everything, no luck.

I tried everything in this thread without success, but did finally get things working. Cost me ВЈ20 for the cable and a lot of wasted time reinstalling the system all over again etc etc. Have reformatted the disk as MacOS extended journaled, 1 partition - disk now recognised. Showed up as having one small partition when installed internally - doesn't seem to cause any problems when connected externally. Read all the stuff in here about new cables etc. No joy - would not boot - got the flashing Folder with question mark. Time came to swap the disks over - ie put the 750 inside the MacBook and take the 500GB out.

EXTERNAL BOOT DRIVE MAC NOT BOOT INSTALL

Formatted the 750GB disk, did a clean install of Mavericks and moved a bunch of my stuff across from the 500GB.Д¬ould happily boot up the new system on the 750GB disk while attached to the USB - SATA interface. I hooked the 750GB up to the MacBook through an external USB - SATA interface.

EXTERNAL BOOT DRIVE MAC NOT BOOT PRO

I wanted to replace the 500GB SATA hard drive in my MacBook Pro with a 750GB disk. TL DR - Make sure you put an insulated barrier between the aluminum surface and your SATA cable electric tapes works fine!Дifferent thing are happening to different people here. I never did throw the old cable back in to test if the tape was a singular fix (I was just happy to see the SSD show up in Recovery again), but I sure kept the potentially-fine cable for a future fix.

I did that and then suddenly the new cable worked, and no more corruption of my installations. The instruction was to insulated the cable from rubbing against the aluminum case by putting a few strips of electrical tape beneath the cable, on the case where the flat SATA cables run. I then read about SSDs not tolerating erroneous data sent along SATA cables very well, with the suggestion that the cable would produce data errors because of it rubbing against the aluminum case. The most recent time, the new cable did not fix the problem. After hours of reinstalling and re-corrupting the MacOS on a new SSD I was installing, I ordered a new SATA cable. I had these issues on two occasions for 13вЂќ Macbook Pros from 2012.

External boot drive mac not boot