Deleted DVD player files accidentally, now Mac displays white folder with question mark on bootup

[AaronM5670]

I accidentally deleted the DVD player app and supporting files in an attempt to save a little space on my hard drive for some important files, and now my MacBook refuses to boot, displaying the white folder with question mark error. How can I redownload these files from Terminal using internet recovery without having to lose everything or reinstall OS X? I am certain this caused the issue.

I really need help on this!

 

[keysofanxiety]

What Mac do you have? You can try hold Alt on startup and see if there's a Macintosh HD partition. If there is, select that with the arrow keys, press CTRL (you'll see the arrow icon change), then press Enter. See if that works.

If not, you can hold CMD + R on startup to boot into OS X Utilities, then select 'Reinstall OS X' and point it to your HDD. This will not affect any documents/apps/data and will only reinstall the core OS components.

I would try both of these steps before doing CMD + ALT + R for Internet Recovery, as Internet Recovery will reinstall the original OS shipped with that machine and might cause complications if you currently have a different version of OS X installed.

 

[AaronM5670]

What Mac do you have? You can try hold Alt on startup and see if there's a Macintosh HD partition. If there is, select that with the arrow keys, press CTRL (you'll see the arrow icon change), then press Enter. See if that works.

If not, you can hold CMD + R on startup to boot into OS X Utilities, then select 'Reinstall OS X' and point it to your HDD. This will not affect any documents/apps/data and will only reinstall the core OS components.

I would try both of these steps before doing CMD + ALT + R for Internet Recovery, as Internet Recovery will reinstall the original OS shipped with that machine and might cause complications if you currently have a different version of OS X installed.

It's a 2015 rMBP running Sierra. No partition is showing up when I hold down alt on startup. I tried using first aid to repair the disk but nothing changed.

Bizarrely, when I select the reinstall Mac OS option, Yosemite shows up - do I need to create a bootable USB disk in this case?

 

[DeltaMac]

Hmmm....
when you hold Command + R at boot, which do you see --- an Apple icon, or a spinning globe?
Apple icon would mean local system, and you should see the system that would be your present installed system to reinstall.
If the spinning globe, that means Internet Recovery, and the system that originally shipped on your MBPro.

Either way, open Disk Utility, and then choose your storage drive from the list. Try the First Aid to repair your storage drive.
You can see how much space is used on your storage drive, also space free. Do you think that is close to what it should be?

 

[AaronM5670]

Hmmm....
when you hold Command + R at boot, which do you see --- an Apple icon, or a spinning globe?
Apple icon would mean local system, and you should see the system that would be your present installed system to reinstall.
If the spinning globe, that means Internet Recovery, and the system that originally shipped on your MBPro.

Either way, open Disk Utility, and then choose your storage drive from the list. Try the First Aid to repair your storage drive.
You can see how much space is used on your storage drive, also space free. Do you think that is close to what it should be?

Cmd-r gets a spinning globe. If I create a bootable Sierra USB drive, does this mean losing all files? Surely there is a way to reinstall DVD player using terminal in recovery mode

 

[AaronM5670]

Delete

 

[AaronM5670]

The command didn't work - I've made a bootable USB drive but the installer is saying I don't have enough free space to install Sierra - what do I do now?!

 

[AaronM5670]

I can see all of my files if I click 'verify' in disk utility, but I can't delete any to make space. The files appear in an 'untitled' mounted drive, which I can't seem to access via terminal.

I think the only option now is a clean install, and rescuing the files on my iMac using target disk mode. Can I do this with a Thunderbolt 2 -> Ethernet adapter and an Ethernet cable?

 

[Fishrrman]

"The command didn't work - I've made a bootable USB drive but the installer is saying I don't have enough free space to install Sierra - what do I do now?!"

You can't boot from the Mac, right?
But you can boot from the USB flash drive, right?
But you CAN'T reinstall to the iMac, right?

OK.

Get a external hard drive, or even a larger-capacity USB flashdrive.

Boot from the install flashdrive, and choose to install a new OS onto the EXTERNAL drive.

Get the external drive up-and-running however you can. You want an external drive that is fully-bootable to the finder with a new account on it.

When you have that done, you'll have a way to boot the Mac.

If you can get it booted, you can then do this:
1. Extract whatever apps and user files you can from it (perhaps copy to the external booter drive)
2. Now, you can boot the Mac from the USB installer, use Disk Utility to re-initialize the internal drive, and then re-install a fresh OS onto it.
3. Then, you can use the stuff you saved on the external drive to re-construct the MacBook's internal drive.

Ahem... in the future, just leave the DVD player app there...

 

[AaronM5670]

I've done pretty much that - copied the entire HDD to an external drive using disk utility, then extracting the required files - thanks for the help.

I definitely won't touch those files in the future..

Now I have another issue..on the fresh install, my admin password is not being recognized by MacOS, despite that being the only account on this Mac. My main account is listed as 'standard', so I don't think there is actually an admin account on there. I've tried entering my username and password on the prompt window, but it's not working. I can't really do anything as a result..

 

[DeltaMac]

I have seen that happen, particularly after a "backup, then format, reinstall OS X, and restore, etc"
And, the fix is to boot to the root user, which will allow you to change your normal user account to an admin account, then restart to log in to your now-admin account.
You have to enable the root user to do this.

 

[AaronM5670]

How do I boot to the root user? I can't enable root user as that requires an admin account and password

 

[DeltaMac]

This page shows how to do enable the root user from single-user mode.
(the account name that you would use to log in to the root user? root

 

[AaronM5670]

This page shows how to do enable the root user from single-user mode.
(the account name that you would use to log in to the root user? root

Thanks very much - it relaunched the setup assistant so I could make an admin account which I used to make my other account admin then deleted. Problem(s) solved, thank you.