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Ashik, Mac Technician
Category: Mac
Satisfied Customers: 11200
Experience:  Bachelor of Computer Application (BCA), 9+ Years of Experience in troubleshooting Macs, iPhone, iPad, iPod etc
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I cant start my mac pro this morning. The grey apple screen

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I can't start my mac pro this morning. The grey apple screen runs with the spinning circle for a long time. I hear the hard drive working.
I tried to do a safe boot and it went on for a long time and then stopped at Disk 3S2:I/O error. It never went past this point.

Now i'm trying to reset the NVRAM. I did the procedure and its been grinding with the spinning wheel for about 10 minutes now. I hear the hard drive working.

Any ideas?
Hi and Welcome. My Name is XXXXX XXXXX I look forward to assisting you today with your question.

Can you hear any small clicking like sounds from the Mac ?
Customer: replied 4 years ago.

No sounds like a hard drive trying to start if thats what you mean

Yes, thats what I meant Steve. Unfortunately, I have bad news for you. This usually happens if the hard drive is failing. The grinding sounds confirms that it is a hardwarwe issue.

Disk 3S2:I/O error indicates that Input Output error, that is your Mac can't read or write files from/to it.

This also happens if the logical structure of the hard drive's corrupted. So lets try running Disk Utility and see how it goes.

Turn your Mac off. Turn it back on and immediately hold down the Command (Apple) key and the S keys at the same time to boot into Single User Mode. Then type the following commands

/sbin/fsck -fy (note the space between fsck and -fy)

If you can't run /sbin/fsck - fy then type only fsk -fy

Hit return and the disk utility should run and let it finish. When it finishes and there is no error, then type reboot and hit return. Let the Mac boot up

Let me know how it goes.

Best Regards,
Customer: replied 4 years ago.

To be clear I don't hear clicking sounds like when a hd is failing. I hear what sound normal like a hard drive working trying to load a program.

Customer: replied 4 years ago.

I did the command S and it showed a lot of text but I can't seem to put any text on the line.

What version of Mac OS X are you using ? What does the last line says ?
Forgot to ask. Did you tried the SMC Reset ? If not, try it. See here :
Customer: replied 4 years ago.


last line says AppleAHCIDiskqueuemanager::setpowerstate(0xffffff8022a28600, 2-> 1) timed out after 100902ms

That sounds exactly like a failing hard drive. It seems like your Mac can't even the read the HD to load the required files to boot into Single User Mode completely.

Restart your Mac and immediately hold down Command and R keys. Does it boot into the Mac OS X Utilities window ?
Customer: replied 4 years ago.

Yes it booted into Mac OSX of some sort. The screen looks normal

Your Mac is booted into the Internet recovery. Select Disk Utility in there and can you see the hard drive in left column ? If so, select it and what's the S.M.A.R.T status ?
Customer: replied 4 years ago.

smart status is failing

it is in red

Steve, now we've confirmed that the hard drive is failing. You have to replace the hard drive. That is your only option. This is a physical problem, not something we can fix online. I'm really sorry that I couldn't solve your problem.

If you've any questions or would like any additional information, please don't hesitate to ask.

Best Regards,
Customer: replied 4 years ago.

So if I get a new hd and install what procedures do I need to do to get it up and running again? will i have to reinstall all my programs again? Is it running with an online boot right now? It looks so normal just slower.

Yes, it is running with online boot. Command R boot into the online recovery. Yes, you have to reinstall everything.

When you install new HD, boot into online recovery, open Disk Utility select the new HD and erase it. Then close Disk Utility and select Reinstall Mac OS X option. This will download Mountaion Lion from Apple's servers and then install it.

Meantime, you should try erasing the hard drive and try to reinstall it on your existing hard drive. Remember, this will erase everything from the HD.
Customer: replied 4 years ago.

This is in a mac pro 8 core with 4 hard drives in the case. I just did a repair disk permissions and it worked?


Customer: replied 4 years ago.

It seems like all my program software is in tact? why is that?

On rare cases, this also happens if the logical struture of the hard drive is corrupted, like I mentioned it in my first response.

What about the S.M.A.R.T status ?
Customer: replied 4 years ago.

SMART status says "failing"

I don't think it is a good idea to contine using that hard drive. You should backup everything ASAP before it dies completely.

Backup everything and replace the failing hard drive Steve. If you don't know what us SMART status, then see below (from Wikipedia)

S.M.A.R.T. (Self-Monitoring, Analysis and Reporting Technology; often written as SMART) is a monitoring system for computer hard disk drives to detect and report on various indicators of reliability, in the hope of anticipating failures.

When a failure is anticipated by S.M.A.R.T., the user may choose to replace the drive to avoid unexpected outage and data loss. The manufacturer may be able to use the S.M.A.R.T. data to discover where faults lie and prevent them from recurring in future drive designs.

Customer: replied 4 years ago.

How would i back up a failing drive?

Get an external hard drive. Then connect it to your Mac and copy all the important files you need to the external hard drive. Don't you have a external hard drive ?
Customer: replied 4 years ago.

Yes I have 16 of them. So I do see the drive in finder. I'm going to save all files. Will that save my programs also?

Great ! Try backing up with Time Machine and that will backup your entire HD including Applications. See here :
Customer: replied 4 years ago.

But will time machine try backing up all hard drives? I just want to back up the main drive

Customer: replied 4 years ago.

it wanted to back up 4 terabits, I don't see an option to just backup the one drive. So I guess I will have to just back up all folders and see what happens

You can exclude the other hard drives from the backup list. Open Time Machine, goto Time Machine menu and select Preferences. Select Option and add the other hard drive to the exclusion list.
Customer: replied 4 years ago.

When I open time machine it opens up into the Today now window there is no place to select preferences.

Select the Time Machine menu and you'll the Preferences. It is in the top left, next to Apple menu.
Customer: replied 4 years ago.

Ok figured that out. Its backing up my main drive. Once done if i install a new HD will it put this back on this drive and everything works again like magic?

LOL No :) You've to restore it to the new hard drive by booting to into online recovery. Do you remember seeing a option named "Restore from Time Machine Backup" when you booted into the recovery eariler ?
Boot into Recovery again, then select Restore From Time Machine Backup. Then follow the onscreen instructions to restore to the new hard drive. Make sure you erase the new hard drive with Disk Utility before restoring contents to it.
Ashik and 2 other Mac Specialists are ready to help you
Customer: replied 4 years ago.

Ok one last question.

Is it better to use time machine to do this or copy and paste files from drive to drive?

Hi Steve, sorry for the delay. That is your choice. Use the method that you're most comfortable with.For a full system backup, use Time Machine.