I have to go in to single-user mode to boot in OS X.

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EtreCheck version: 2.6.6 (226)

Report generated 1/10/16, 12:22 PM

Runtime 1:46

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iMac (27-inch, Late 2012)

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iMac - model: iMac13,2

1 3.2 GHz Intel Core i5 CPU: 4-core

8 GB RAM Upgradeable

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NVIDIA GeForce GTX 675MX - VRAM: 1024 MB

iMac 2560 x 1440

System Software: (What does this mean?)

OS X El Capitan 10.11.1 (15B42) - Time since boot: less than an hour

Disk Information: (What does this mean?)

APPLE HDD ST1000DM003 disk1 : (1 TB) (Rotational)

EFI (disk1s1) <not mounted> : 210 MB

Recovery HD (disk1s3) <not mounted> [Recovery]: 650 MB

Bootcamp (disk1s4) /Volumes/Bootcamp : 300.00 GB (120.62 GB free)

Macintosh HD (disk2) / : 811.83 GB (454.27 GB free)

Core Storage: disk0s2 120.99 GB Online

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EFI (disk0s1) <not mounted> : 210 MB

Boot OS X (disk0s3) <not mounted> : 134 MB

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Core Storage: disk1s2 699.35 GB Online

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Jan 10, 2016, 12:18:39 PM Self test - passed

I have only mentioned using Terminal once, I used Terminal in the Recovery Partition to change the date, month and year. I do know what this command does. I am always responsible of what I do in Terminal and this is the only thing I have done so far and tested multiple times. I found this code on another apple support discussion. How to set system time from Terminal while booted from 10.6.3 server install disk?

And this discussion too: OSX Mavericks - "An Error occurred while preparing the installation. Try running this application again."

The other code I used and still using to boot in OS X is in single-user mode, not in terminal. And this code I have not found on the internet. This code is: "/sbin/mount -uw /". This just mounts the root device and then the other code I use is: "exit", this let's me get in to OS X. These 2 codes is what I need to do in single-user mode to boot in OS X.

I am very thankful for you to be helping me right now. 🙂

Loner T wrote:

Let us leave the OS X installation on the internal disk alone. Install a fresh copy of OS X on an external disk using Internet Recovery. You can use a USB flash drive, but it will be slow. a FW/USB2 (or USB3)/TB HDD is recommended.

Please see How to install OS X on an external drive connected to your Mac - Apple Support .

I am sorry to say this but are there any other ways. This seem a little bit over the top and now I don't think I mind typing in the 2 codes in single-user mode everytime I want to boot in to OS X. I have done fresh installs many times before but never on a macintosh, only on a windows machine. If there aren't any ways then I might consider doing this. I do have to wait a bit though because I borrowed my 8 GB USB stick to a friend of mine. I have a 32 GB at the moment but that has the windows 10 ISO on it. I would prefer to do it on the 32 GB USB. So I am going to wait to get the 8 GB back and make that the windows 10 ISO and then do a fresh install on the 32 GB (better capacity is better).

When I try to boot onto Safe Mode, the same thing happens when I try to boot in normal mode. I press the power button > I hold down the shift key > I hear the chime and white screen > I see the apple logo and the progress bar > the progress bar only gets to 3/4 of the way and then the computer shuts down.

I have tried both in the past when I started having this problem. The only way for me to boot in OS X right now is to go to single-user mode and type "/sbin/mount -uw /" and then "exit". So I booted in to OS X and opened Disk Utility. I ran first aid on Macintosh HD and I get "First Aid process is complete, press Done to continue." After that I tried to boot in OS X again without holding down Command + S but the same problem occur, the computer shuts down when the progress bar gets to 3/4 of the way.

I then proceed to boot in recovery mode. I click on re-install OS X. My computer's eligibility had been verified. I then sign in with my apple ID. I accepted the terms of service and it began downloading, not one second later I get a pop-up saying: "An error occurred while preparing the installation. Try running this application again." This has happened before and I did some research about it and most of it were saying that the date on your computer was wrong and you can change it in Terminal in the Recovery Partition. My date wasn't wrong but I still changed it but I got the same error message.

So right now I don't think it is a hard drive failure. Because Bootcamp is working just fine on my computer. But I think the HDD is not mounted properly for OS X to boot? I would really appreciate your help for solving this problem.

Oops, sorry about that. I did boot in OS X and ran first aid on my hard drive and THEN go to recovery mode. But this time I went in to Recovery Mode and then ran first aid on Macintosh HD and I got the following message:"First Aid process has failed. If possible back up the data on this volume. Click Done to continue." I don't worry much about losing my data because I have a backup external hard drive. What I have realized as well is that there a disk image called: "Apple disk image Media." And under that image there is partition that is called:"OS X Base System."

I can't make an appointment to an Apple Store, because I live on a small island and there is no Apple Store on this island.

Can you enlighten me more on what you mean by "Have you split your fusion drive?"

So if there is no solution for this, is it safe to just keep inserting "/sbin/mount -uw /" and "exit" every time I want to boot in OS X?

Another question that I have is how could this have possibly happen? I barely use OS X, I mostly use bootcamp to play videogames. And I am always aware of what I am downloading on OS X and Windows.

LexSchellings wrote:

Yes it is about the same.

You do not quit with "exit" but with "reboot".

After typing and pressing enter on: "/sbin/mount -uw /". I have to type "exit". Here is the reason.

If I type "reboot", de computer will shut down and then turn itself on. When it turn itself on, I hear the chime, then the apple logo and progress bar appear, the progress bar gets to 3/4 of the way and then the computer shuts down by itself.

If I type "exit", de computer will just get in to OS X right away.

Sorry for the late response. In summary I just don't want to insert "/sbin/mount -uw /" and "exit" every time I want to go in to OS X. I hope you can help me with this because it has been like this for almost a month now and I haven't found a single solution yet.