Just installed a new hard drive into my MacBook

[Ad18]

I replaced my hard drive with a seagate 1TB SSHD SATA 2.5". I have a backup of my computer on an external hard drive. I am getting a grey screen with a question mark inside of a folder when I start up the computer. What do I need to do next?

 

[T5BRICK]

What do I need to do next?

https://support.apple.com/en-us/HT201314

If your Mac supports internet recovery, use that. If it doesn't, you need an OSX install disk that is new enough to support your Mac.

 

[Ad18]

I have started it in recovery mode, but the internal hard drive isn't showing up.

 

[DeltaMac]

New hard drives never come prepared for installing OS X.
A simple erase will take care of that.
While you are booted to internet recovery, go to the Disk Utility, and erase your new hard drive.
Then, your hard drive will show up as a choice for the install.

 

[Ad18]

New hard drives never come prepared for installing OS X.
A simple erase will take care of that.
While you are booted to internet recovery, go to the Disk Utility, and erase your new hard drive.
Then, your hard drive will show up as a choice for the install.

It is giving me an error message when trying to erase

 

[Ad18]

It is giving me an error message when trying to erase

Or partition

 

[dukebound85]

Did you format the drive and install OS X? Have you set it as your start up drive?

 

[Ad18]

Did you format the drive and install OS X? Have you set it as your start up drive?

I tired to install it, it isn't showing up when I go to pick a disk. I haven't done anything with the start up drive

 

[CoastalOR]

OP,
Here is a link to an Apple Support Community post that may or may not apply (it is hard to say since you do not provide much basic information such as: what model/year/size MBP, which OS are you trying to install/restore, what format is your back up, can you boot from your back up, and what specifically is the error message you get when trying to erase or partition):
https://discussions.apple.com/thread/5908402?start=0&tstart=0
Good luck.

Edit:
Here is another thread that might be useful:
https://forums.macrumors.com/threads/help-new-1tb-seagate-sshd-wont-boot-in-my-2010-mbp.1592098/

 

[DeltaMac]

It is giving me an error message when trying to erase

What is the error message that you get?

Boot to the recovery system.
Open Disk Utility.
Click on the hard drive part number line, then click the Partition tab,
Choose 1 Partition from the Partition Layout drop-down. Click Options to make sure that the format will be GUID.
Check that the Format will be MacOS Extended (journaled)
Name the partition, if you like, then click Apply.
If you get some error message, then the common culprit can be the SATA drive cable. You should try replacing that.