MacBook won't start but I need to backup my data

First off, you need to ascertain if it is OS, drive or logic board damage. If the Mac is connected to the Internet and you reboot holding Option-Command-R, can it boot in Internet Recovery Mode? If it can't then it is Logic Board and the Mac is hosed cause Apple won't service it anymore and there are no spare parts. Can take the drive out, put it in an enclosure and use that to salvage whatever from another Mac.

If it does boot, can get an external drive, format as GUID/Apple Extended (erase the partitions first to avoid the permissions error), then install the OS from Apple's servers. Boot from there, and when it starts, let Setup Assistant migrate the stuff from the internal drive onto the external. If successful, that would be the best way to salvage the most. Else, salvage what you can manually. If you can't salvage anything, then it's a Drive Failure, so get a new one and replace/reformat/reinstall the internal. If you did salvage, erase/reformat the internal and reinstall the OS there. It would mean it was an OS failure: migrate your stuff back in when it restarts and Setup Assistant kicks in.

Hi Kim, Thanks will try this method to rule out faulty drives. Someone in a different thread (Internet recovery isn't working.) is positive that it's a problem of the heat paste between the graphics chip and heat sink drying up.

When you select the device itself in Disk Utility's window (not the volume which is indented underneath), the info section on the bottom should tell you what Partition Map scheme the drive has. You need GUID for the Mac to be able to boot from it. Try clicking on Erase while the device is selected, you will get the option to choose the Partition Map scheme (by default, Windoze drives come in MBR, with NTFS format).

Once properly formatted, can quit Disk Utility, choose Install Mac OS in Internet Recovery's main menu, then choose the newly formatted drive as a target at the start of the installer.

Once installation is complete, that newly-installed drive should be the default chosen by the Mac's boot loader when starting up. If not, press Option before the startup chime and select from the list.

Don't use or know TM. Even in my worst mechanical drive days, migrating 500 GB took at worst 2-3 hours. The fact it is taking so long appears to point to a drive failure as the root of your problems. If migration can't conclude and you cannot manually drag what you need over to the external once migration is aborted and the Mac finally finishes booting up, then there is reduced hope that you can salvage your files.

Pictures? As in an iPhoto/Photos library?

So... how are we doing?

Forgot to mention that, in view that the drive is very probably bad from what we've gathered thus far, once it has been replaced and the Mac is back up with its internal drive, bereft of its contents while the corpse lies outside in an antistatic bag, there are a number of businesses that can do data recovery if the information is worth the cost.

I have the same problem with my MacBook Pro (grey screen - tried everything to fix it), but I have managed to back-up my data however. I took my drive out (an SSD drive) and I used a SATA to USB-adapter/cable to hook up the drive to a different MacBook where I simply copied everything in finder.

Hi Balt91:

If you were a able to use a USB to SATA adapter to copy your data to a different computer, have you tried connecting it to your own computer and holding down Option key while booting. This should allow you to boot from your external drive. If it boots ok, then the problem may not be your hard drive but could be the drive SATA cable inside computer.

Kim