I am trying to send an apple computer in for repairs. It is asking to back up the system, not sure how to do that since the computer will not turn on? Please advise

Do you have another Mac? If you do see if the problem Mac can boot into Target Disk Mode. It is can you can connect the two Macs together as described in the link I provided and backup your user data to an external drive.

If it won't boot into Target Disk Mode you're pretty much forced to send it in the way it is. Do you know generally what is wrong with your Mac?

Please read the following user tip and state the problem in detail: 

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