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levmc

macrumors 6502a
Original poster
Jan 18, 2019
687
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My MBP isn't booting (or rather shutting off as soon as it boots) because the internal drive is almost full. So before attempting powering it on again, I would like to move access and move some of the files to my external HDD. How do I go about doing that?
 
What cable? I do have iMac that I can connect it to.
It's mid-2014 MBP.
 
You would connect the MBP to the iMac with a USB3 cable. Then when booting up the MBP, hold down the T key. That should boot it into target disk mode. The iMac should see the MBP as an external USB drive. Google ‘Target Disk Mode’ if you run into any problems. Good luck!
 
Hmm, but then I would have to buy the cable. How would you do it if you don't want to use the iMac in the process and just use external drive?
 
Hmm, but then I would have to buy the cable. How would you do it if you don't want to use the iMac in the process and just use external drive?
You don't.

The only option is placing the internal drive of the laptop into an external drive enclosure to connect to the iMac to transfer files, or connecting it to the iMac directly with a cable and transferring the files.

The cable is cheaper than the drive enclosure, and a lot easier to do.
 
Apple's support page for this feature has more details: https://support.apple.com/HT201462 - in includes a description of what cables can be used and those that cannot. A USB-A to USB-A cable cannot be used.

An alternative to using Target Disk Mode would be to create a bootable external HD. However, since you have the iMac, Target Disk Mode tends to be the more direct route.
 
There is another possibility. If you have a USB3 flash/thumb drive (16GB+), you could install MacOS on that then use it to boot up your MacBook. Just plug it into the MBP and hold down the Option key when you boot, then select the flash drive. You would need another drive for the files you move from the internal hard drive.
 
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Apple's support page for this feature has more details: https://support.apple.com/HT201462 - in includes a description of what cables can be used and those that cannot. A USB-A to USB-A cable cannot be used.

An alternative to using Target Disk Mode would be to create a bootable external HD. However, since you have the iMac, Target Disk Mode tends to be the more direct route.

From the website:
"
If one or both computers has a Thunderbolt 3 (USB-C) or USB-C port, you can connect them as follows:

So for a 2014 MBP and 2017 iMac, which of these 4 choices would be good?
 
I think you would use a USB-C to USB-A cable from iMac to MBP.

”To connect a USB-C port to a USB-A port, use a USB-A to USB-C cable that supports USB 3.0 or USB 3.1”
 
I think you would use a USB-C to USB-A cable from iMac to MBP.

”To connect a USB-C port to a USB-A port, use a USB-A to USB-C cable that supports USB 3.0 or USB 3.1”

Would this be the same kind of cable used to charge newer phones? I guess I could just use the cable that came with my Android phone then?
 
That cable only does USB 2.0 data. You want USB 3.0 data (5Gbps), so this one will work:

 
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OP:

Don't make things too hard on yourself.
If the drive won't boot because it's "too full", the simple solution is:
Boot from ANOTHER drive, then delete a lot of stuff.
Now, the internal drive should be "re-bootable" on its own.

The easiest way to create that bootable drive:
- Get an USB flashdrive 32gb or larger
- Boot to internet recovery on the iMac
- Use internet recovery to install a bootable OS to the flashdrive (NOT to the iMac!).
- Set it up with a basic account -- username and password is all you need.
- Use this to boot the MBP
- Once booted, you can now access the MBP's drive and delete files. You will need to select the icon of the internal SSD, then do "get info", and then put a checkmark into "ignore ownership on this volume". Now you can delete whatever you wish.
- BE CAREFUL what you delete. I would get rid of movie files first, because they're the largest and removing them will "clear up" space quickly.
- Once you have about 20gb of the SSD "free", now try rebooting the MBP on its own.

One more thing...
In the future, BE MINDFUL of "how much stuff" is on your internal drive. You probably want to keep around 15gb "free", so that the OS "has room" to do the things it needs to do (stuff that is "normally invisible" to the user).
 
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Another thing to consider once you get all this sorted out is that replacing the SSD storage drive on that MacBook Pro is insanely easy.

OWC sells very affordable SSD storage drives, and a fairly inexpensive external SSD enclosure kit to put the old one in and use as extra backup. The linked kit is the one I got over a year ago and it has worked great since I replaced the internal drive on my 2014 MBP with a 1TB SSD.
 
That cable only does USB 2.0 data. You want USB 3.0 data (5Gbps), so this one will work:


Ok, I got the cable and connected it.
I started the target mode but I don't see it in the Finder.
 
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Ok, I got the cable and connected it.
I started the target mode but I don't see it in the Finder.
You said your MBP wasn’t booting because the internal drive is full. What made you come to this conclusion? Is it possible the drive is just dead?
 
I've said it before, and I'll repeat:
The MBP owner needs to boot FROM ANOTHER DRIVE, get booted to the finder, and then:
- see if the internal drive can be mounted on the desktop
- if it can, can it be accessed?
- If it can, can files be deleted until about 20gb is free?
- Once that's done, can the owner run disk utility's "first aid" option on the internal drive?
- If that can be done, can it now boot "by itself"...?

By "from another drive", I DO NOT mean "target disk mode".
The owner needs to connect another bootable drive to the MBP, and boot from the MPB itself.
If the owner doesn't HAVE another bootable drive, he needs to MAKE one.
 
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