Mid 2010 MacBook Pro won't boot past blue screen

I've been having problems booting up my MacBook. I can't get past the blue screen. It went from booting slow at the grey apple logo screen to not booting up at all. Is it a problem with my hard drive? I also have boot camp running as well, but I can still see the boot camp drive for windows and my OS X drive, as well as my installation disk when I have it inserted when I hold the option key at start up.
I'm still able to run windows on it without any problems when I pick the windows drive. I tried different methods from different forums but I'm just not getting through. I tried holding 'c' to boot up from cd and I let it run over night but it never got past the grey apple screen with the gradient wheel (still spinning). I had already used time machine to back everything up before this happened since I was able to boot up properly (but slowly). Can anyone help? It's driving me nuts, and I can't remember what os/firmware version I'm running.

n your signature you said you are running 10.6.3.  So let’s assume you are running Snow Leopard.
It sounds like your diagnosis of disk problems is correct.  The OS X partition may be corrupt.
Try booting in Safe Mode.
http://support.apple.com/kb/HT1564
Try again to boot in normal mode.
If it will boot in Safe Mode but not in normal mode then you could have some 3rd-party software preventing the boot or you could have a corrupt disk or OS.
Boot as from the startup manager (Boot - option) and then select the installation disk.
Hopefully that will work better than starting with the Boot-C option.
Then try to repair the system disk.
Start the Disk Utility.
Perform the steps in http://support.apple.com/kb/PH5836.
If it repairs OK but still won’t boot reinstall OS X.
Installing Mac OS X 10.6 SnowLeopard
http://kb.iu.edu/data/akav.html

Similar Messages

  • Macbook Pro won't boot past grey screen with Apple logo and then shuts off

    This is a long story...
    This morning, I would turn it on and it'd go to the grey screen with the Apple logo for a few seconds and then go to the icon that is a circle with a line through it. After reading online, I was able to boot it up in Safe Mode. I messed around a little bit in system preferences thinking I could fix it on my own, not really knowing what I was doing (I'm a *******). I went to Startup Disk in Preferences. I chose the MAC OS X, xxxx and then clicked the lock to prevent further changes and then clicked restart.
    Now when I turn on the macbook, it goes to the grey screen with the Apple logo for at least two-three minutes and then just shuts off. Won't boot into Safe Mode now. Please help. I already tried the Command-Option-P-R keys trick like five times.

    If you have a full retail DVD for 10.6 you can boot from that by holding the C key during startup...but you will then be in install mode if that is what you want to do.  At least go ahead and see if it will boot ok from the 10.6 disk and then you can decide what you want to do further.
    Apple does not have 10.5 for sale anymore from what some other users have said on here so if you want to go that route you will have to find a copy for sale such as from eBay or one of the Mac resellers.
    Before taking the machine to someone, try booting from 10.6 and see if that works...that way you can narrow down problems the machine may be having.

  • My Mid 2010 MacBook Pro will not boot

    My Mid 2010 MacBook Pro will not boot regularly, in safe mode, in recovery mode or from original OS DVD. Is this the logic board?
    I've tried resetting the SMC and pram numerous times and even tried switching out hdd's to try and do a clean install on a new hdd.
    If I attempt to boot regularly or from recovery drive the grey apple logo appears for a period before the screen goes black and the power LED operates as though in 'sleep' mode. I'm unable to wake it from this state and the same applies to booting in safe mode.
    When attempting to boot from the OS DVD that was originally packed with the computer it just freezes on the language select option, this occurs with the other hdd's I have attempted to use.
    Any other suggestions to get it working? I fear the logic board has gone and that the repair won't be worth the money.
    Thank you in advance.

    Hi JRC8.8,
    It sounds like you have been on the right track in trying to troubleshoot this issue. You may want to see if your MacBook Pro will boot directly to the Apple Hardware Test, as outlined in the following article:
    Apple Support: Using Apple Hardware Test
    http://support.apple.com/kb/ht1509
    Regards,
    - Brenden

  • Mid 2006 Macbook Pro won't boot (from HD or optical)

    My mid 2006 Macbook Pro will not boot from the hard disk, or from the internal DVD. I am currently running the latest version of Lion (10.7).
    I tried searching the forums and found a similar issue here:
    https://discussions.apple.com/thread/1687899?start=0&tstart=0
    But that was with a Mac Mini. And it doesn't look like the OP issue was ever resolved. I am having the exact same problem.
    When attempting a normal boot from the internal HD of the Macbook Pro. It will make the happy chime of a successful POST. It will display the Apple logo. And that's as far as she gets.
    No spinning wheel, no error image, no nothing. Eventually the system will start spinning up the fans as if it were under load (this was after about a half hour of just letting it sit there).
    Doing a verbose boot, it never went past this:
    com.apple.driver.Apple.IntelCPUPowerManagement
    Photo of verbose boot:
    Here's what I've tried.
    1. Bought a brand new battery (as the current one was at death's door)
    2. Zapped PRAM (Apple + Option + P + R)
    3. Reset SMC according to these directions: http://support.apple.com/kb/HT3964?viewlocale=en_US
    4. Attempted to boot to my original Tiger (10.4) install DVD, only to stop at this point during a verbose boot (Apple V):
    Extension "com.apple.driver.AppleACPIPlatform" has immediate dependencies on both com.apple.kernel and com.apple.kpi components; use only one style
    Photos:
    5. I am able to put her in Target Disk Mode (hold T at boot). Then with a firewire cable I can connect it to my wife's Macbook 13" and I am able to run disk utility on it! Disk Utility did find and repair errors, however, it still refuses to boot.
    6. I attempted to boot from my wife's Macbook 13" in Target Disk Mode. I put her machine in Target disk mode. Connected the firewire cable. Powered on my 15" MBP while holding the option key. Then I selected her drive as the boot disk... however it still refuses to boot even from a known working HD.
    7. Finally, I swapped around RAM DIMMs with no change in behavior.
    Help! I know she's an older gal (Laptop is 6 years old now) but I'm not exactly flush with cash and would rather not give up on her just yet.

    My Mac started freezing (colored pinwheel) every time I tried using any application (i.e. Safari, iPhoto). After restarting for the 2nd time, it would no longer boot - makes start up sound but gets stuck on gray screen w/ apple icon.  I tried resetting PRAM also - did nothing. I decided to reinstall OS; problem now is my HD is nowhere to be found! I am a tech dummy so this is way beyond my comprehension...I'm not seeing my HD from the Disk Utility either??? 
    Side question...I backed up my files (mostly pics JPEG and videos) on DVD (had to compress to save). Why can't I open files on PC?

  • My Macbook Pro won't get past white screen....

    My Macbook Pro is stuck on the white screen with the gray apple logo and loading gear spinning below---for hours now. Restarted multiple time without any change. Agh!

    Boot in safe mode. First, disconnect all wired peripherals except keyboard, mouse, and monitor, if applicable, and remove all aftermarket expansion cards. The instructions provided by Apple are as follows:
    Be sure your Mac is shut down.
    Press the power button.
    Immediately after you hear the startup tone, hold the Shift key. The Shift key should be held as soon as possible after the startup tone, but not before the tone.
    Release the Shift key when you see the gray Apple icon and the progress indicator (looks like a spinning gear).
    Safe mode is much slower to boot and run than normal.
    If you can boot in safe mode, try rebooting as usual (i.e., not in safe mode.)

  • PowerBook G4 won't boot past blue screen

    I've read a couple of posts with similar problems. The jist is, I did a security update/restart earlier and now my laptop won't boot past the blue screen after the white screen with the gray apple. I think I'm on Mac OS 10.4.11 but I had it on auto-update so that could be incorrect.
    I've booted from the install disk and run a diagnostic from the First Aid bit in the Disk Utility. It says that there are no errors found and the S.M.A.R.T. status says "verified" as well. It won't let me boot into Safe Mode (although, I could be doing that wrong as I'm not exactly clear on how to do it - pressing S doesn't seem to do anything, but if I press Command + S it takes me to a text listy thing and I've run the "fsck -f" system check (which seems like the same as the disk utility check?) from there and also gotten the "volume is ok" message. There was also a suggestion to run some kind of diagnostic after booting with the D key from the install disk, but I was never able to get the disk to boot from the D key, only the C key.
    I'm sure that this is kind of the "same song, different verse," kind of post, but I've not read about volumes registering as okay. I'm a little wary of a archive-and-reinstall as I've not ever done that before (so, if that's the suggestion you have, I would really appreciate loads of specifics on how that works so I don't mess up!)
    I've read in several instances suspicion of a hard drive problem but I've not had any slow downs or any crashing. I did travel to the UK for about 10 days, but I didn't even change the time zone on my laptop while there, so I don't think that's it (but I suppose it could be.)
    Lastly, I did recently replace my keyboard. A few keys had become non-responsive so I replaced it and have had the new keyboard for a bit over a month.
    Suggestions? Ideas? Sorry if it's a repeat post -- just felt like the circumstance was a teensy bit different. And also, thanks very much for any info you can give.

    Linsey:
    If you can boot your computer into Firewire Target Disk Mode and you have access to a second Mac that supports firewire, you may be able to back up items that have not been backed up previously.
    If you are able to back everything up successfully, and you have tested your backup to be sure it is sound, then we can proceed with re-installation of the OS. The best option is to completely reformat and erase the HDD and then install the OS from disk. (I will post complete step by step directions). This will enable you to start with a clean slate/HDD. Your other option would be to use the Archive and Install option. Think it over and let me know how you want to proceed.
    cornelius

  • Why is my mid-2010 macbook pro having trouble booting and crashing?

    I have a mid-2010 13 inch macbook pro that has recently began to have severe problems. It started after I shut it down one night and woke up to the sound of my mac's fans running loudly and my computer running extremely hot. Apparently, it must not have finished shutting down that night and something went wrong with it when i closed the lid. Ever since then, the computer will either take a long time to boot up (the apple symbol will take up to a minute to appear, and then up to several more minutes to go to my desktop) or it will display an error (either the folder icon appears instead of the apple logo, or the apple logo appears and then after a minute or two is replaced by the circle slash). Once i'm in, the computer seems to function normally, but anytime it needs to access the disc there might be another delay, or the computer will freeze, forcing me to shut it down again. The most common time this occurs is when I am waking the mac from sleep. In addition, the cpu would run hot (~85) which would imply i was doing high cpu activity, except i was usually doing very little, activity monitor showed low levels with sudden intense spikes whenever i did something.
    I've run several diagnostics to try and determine the problem, but none identified an error:
    booting computer from different computer/startup disk - runs fine (apparently. gave my mac to someone else to try this test, could not see results for myself)
    Thorough Apple hardware test: no problems found
    disc utility: disc/discpermissions verified and repaired with no issue.
    PRAM/VRAM reset: actually sped up the lagging of the system once it reached the desktop and intense cpu thing but booting problems still persisted.
    archive and install: some of the time it would fail to install in the middle of the installation, forcing me to start again, but once i completed it, issue still persisted.
    clean wipe of drive with restoration from time machine: computer speed better but still trouble when booting.
    Clean wipe of drive without migration of data: computer running and booting quickly, but occasionally still received circle slash instead of apple logo.
    At this point, i don't know where the source of the problem lies. The computer is old, but has never had an issue until recently. The problem is inconsistent, and all testing implies it doesn't exist, which makes its diagnosis extremely difficult. As it is a 2010 mac, it is clearly out of apple care and warranty so i cant go to a genius. I have a weak battery (80%) and my screen lid is a little loose from frequent use, but those are the only blatant problems i'm aware of with my mac.
    Any suggestions? I can gladly provide more info as needed.

    When you have the problem, note the exact time: hour, minute, second.  
    These instructions must be carried out as an administrator. If you have only one user account, you are the administrator.
    Launch the Console application in any of the following ways:
    ☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
    ☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
    ☞ Open LaunchPad. Click Utilities, then Console in the icon grid.
    The title of the Console window should be All Messages. If it isn't, select
              SYSTEM LOG QUERIES ▹ All Messages
    from the log list on the left. If you don't see that list, select
              View ▹ Show Log List
    from the menu bar at the top of the screen.
    Each message in the log begins with the date and time when it was entered. Scroll back to the time you noted above.
    Select the messages entered from then until the end of the episode, or until they start to repeat, whichever comes first.
    Copy the messages to the Clipboard by pressing the key combination command-C. Paste into a reply to this message by pressing command-V.
    The log contains a vast amount of information, almost all of it useless for solving any particular problem. When posting a log extract, be selective. A few dozen lines are almost always more than enough.
    Please don't indiscriminately dump thousands of lines from the log into this discussion.
    Please don't post screenshots of log messages—post the text.
    Some private information, such as your name, may appear in the log. Anonymize before posting.

  • Mid 2010 Macbook Pro won't switch to Nvidia graphics.

    I have been playing Starcraft II on my Macbook Pro (i7/4G RAM/15" Display) for a few weeks now. Yesterday my frame rates dropped through the floor. The game was nearly unplayable. I thought initially that the level I was playing just had too many units. I re-played one of the tutorial levels and it too was slow. I lowered the graphics quality settings in the game and it didn't get much better.
    I put the game into windowed mode (rather than full screen) and started playing. I pulled up the system profile tool and saw that the intel graphics were active, not the nvidia graphics.
    I went into system preferences/energy saver and shut off automatic graphics switching and it was still using the Intel HD graphics.
    This happens all the time, plugged in or not.
    Any ideas?

    Thanks for your suggestions. I ended up taking it to an Apple store and they ran diagnostics on it. It came up clean.
    The tech powercycled it and cleared the PRAM (?) by holding cmd-option-p-r while booting.
    I am not sure what fixed it, but Starcraft 2 framerates are back where they used to be.

  • Help! Mid 2009 MacBook Pro won't boot! Just apple and the wheel keeps turning... Out of AppleCare , survived the hurricane, NOW WHAT?

    Won't boot. Won't turn off. No sounds. Just wheel turning around and around. What to do???

    Don't turn it off, perform a emergency backup proceedure to a new drive.
    Emergency backup procedure
    Drag and drop copy your users file folders (music, pictures, documents etc) to a regular external powered drive as soon as possible.
    Do not use, setup or trust only TimeMachine at this troubled time as it will copy corrupted data and we need just your users files safe just in case. TimeMachine cannot be used with a Windows PC.
    Unmount (right click > eject) and disconnect all external drives once the backup process is completed.
    Note:
    If you have any over 4GB sized files, those won't copy to a standard formatted FAT32/MSDOS drive from the factory, if you need to save these 4GB+ files use another blank/empty drive and use Disk Utility to format it 1 Partition, Option: GUID,  Format: OS X Extended Journaled.
    Typical large 4GB+ sized files are movies, imovie projects and raw (non-compressed) audio files. Naturally if you don't have any of these or can avoid backing them up (like you don't care about them) then there is no need to reformat the drive from FAT32/MSDOS.
    Mac's cannot copy to nor format a NTFS  drive. ExFAT format to be used with a Windows machine must be right click formatted by Windows, not OS X (does it wrong) XP machines can install a free exFAT update from Microsoft. Vista-Win 8 can format exFAT.
    Formatting a drive will erase all data on it.
    Once the backup is completed, you can take your machine to a local PC/Mac tech and they can solve your software and or some hardware issues, but if a hardware issue is determined, you should take it to Apple first as they have the electronic checker.
    If you get a new machine, drive or new OS X installed as a result of this problem, then you can access your external drive backup and restore just your files if the tech support won't or you rather do it yourself for privacy reasons.
    1: Connect the drive and click on the icon and Finder > Get Info
    2: At the bottom unlock and "Ignore Permissions on this volume" provide your Adim password.
    3: Once your files are transferred to the new account, then perform #6 Reset User Permissions here
    ..Step by Step to fix your Mac

  • Mid-2010 Macbook Pro Randomly goes back to login screen?

    My mid-2010 MBP will randomly log me out.  I'll be on the internet or working on a paper and it will go to the blue screen that occurs when you're booting up the computer and then to my login screen, where I have to type in my username and password again.  Anyone else experiencing this?

    eedaley wrote:
    Anyone else experiencing this?
    Hi e,
    No, but try a Safe Boot:
    http://docs.info.apple.com/article.html?artnum=107393

  • MacBook Pro does not boot past apple screen after replacing hard drive

    After replacing hard drive on MacBook Pro 13 inch early 2011 model, the screen only boots to the apple logo.  Do I need to re-install the OS?

    The problem is that the OS is not in any where else of the MacBook Pro than in the HD / SSD. If you replace the Hard Drive, then you will need to Re-install OSX into that hard drive, it's pretty easy.
    1) Power up your Macbook Pro, as fast as you can press and hold the Option key (ALT). You'll see that it opens the bootable-devices you have, you'll see a Recovery partition, click it.
    (If the Hard Drive contains data do the following)
    2) In the menu select Disk Utility.
    3) In Disk Utility go ahead and select the Hard Drive that is inside the MBP.
    4) Erase the content.
    (If the Hard Drive contains no data continue with the following jumping the last 3 steps).
    5) Select Re-install OSX.
    6) Select the Hard Drive in which you want to install it.
    Follow the steps of everything else (it should take approximately 1 hour to do the whole thing).
    Hope this helps!
    Later.

  • Late 2008 MacBook Pro won't boot; only gray screen with Apple, spinning gear, and then the mouse pointer.

    Thanks to all in advance! Okay, last night I was trying to encrypt a Time Machine BackUp disk (Seagate 500GB Back Up Plus) and a dialog box popped up and said "POSIX could not..." And then whatever was next. So I unplugged the drive, plugged it back in, and the files still showed up, so I was like "oh okay so it's not screwed up." The next I try and boot my MacBook Pro, and of course it doesn't. The gray screen comes up, the logo shows up, the gear is spinnin, the it goes away and the mouse shows up. But that's where it stops. And sits. And sits. And sits. So I force it to shut down. I run through this many more times, as well as attempting the Recovery Mode, Safe Boot, and to no surprise, it doesn't work. So I go grab my trusty Snow Leopard disc, pop it in, ctrl-C on start up and it loads. So I select the option of restoring from a Time Machine backup and plug in the external drive only to not see it in the list. So I go to Disk Utility, and find out that the entire external drive has been erased and renamed disk8s2. So I go to my internal drive, but it shows how much has been used and it matches to how much as of last night. So I tried repairing the disk and restarting and of course it doesn't work. So now I don't know what to do. Really I'll take any suggestions besides buying anything (I'm only a 16 year old guy haha). So yeah. Thanks!

    The encryption never actually followed through.
    You started it, though. That makes the volume inaccessible to any OS X version before 10.7.

  • 14" iBook won't boot past Blue Screen?

    Hi,
    I have in my possession my Sisters 14" iBook G4. It boots with the grey Apple logo but then freezes at the blue screen. I'm guessing it's either the hard drive or logic board, does anyone have a procedure to follow to diagnose the fault? I don't have the original discs but do have a 10.5 retail box.
    Thanks in advance.

    Spudnuty - I think you might want to hear this...
    I just bought an ibook G4 1.2Ghz "Late 2004" model off of ebay, had the blue screen problem. I bought it because I thought it might have been the OS (freeze at login) and the previous owner didn't know, but it was an actual freeze... actually froze a few times while at the spinning wheel at startup, and would randomly display a dark blue screen sometimes at startup.
    I am an ACMT, I decided to disassemble the machine as per the service manual and get it down to basically the logic board, even pulled off the top display entirely. Ran an external monitor via mini-VGA, external HD via Firewire... still froze at blue screen. So I decided something similar to your suggestion - I pulled off the heat sink, only to discover that the conventional way of cooling a cpu/gpu (heating compound directly under heat sink) had been abandoned on this model for some crappy adhesive pads. The pads had a bit of thickness to them, so I decided to cut of a small section of the top shield, fold it into a nice square and flatten it. I then put some heat sink compound on both the cpu and gpu, put the metal "shim" on the gpu and tightened down the heat sink. Guess what? Started up in a jiffy. I put a fresh install of Tiger on it, have been playing multiple Quicktime vids looped for a while now... machine is going strong.
    All that to say, shimming works on these later ibook G4 models that get the blue screen, I've confirmed it. Just remove the adhesive pads, shim with something heat conductive (maybe even aluminum foil!), add heat compound and run it for a while.

  • Mac pro won't boot past grey screen because of bonehead move?

    Hey everyone,
    So today I wanted to free up Macintosh hd space to have room to install new software I purchased. During trashing certain files, I noticed there seemed to be a duplicate folder of library so I decided to trash that duplicate library folder. When I went to go empty the trash consisting of library and other various files, the trash button would not work. It would press in but nothing would happen. So I decided to reboot the Mac pro and when it turned on, I got the gray screen with the apple logo, folder with question mark flashing. Did I delete something I wasn't supposed to? What should be my next step in solving this issue?
    Thanks

    Before you do some heavy maintenance, clone your drive, maybe just get a larger drive and clone, then use the old original as backup.
    Restore everything from the trash of course for starters. But a new drive or two would also be a good idea. Then buy Disk Warrior and SuperDuper to handle maintenance and backups.
    If you had TimeMachine running you might also recover files.
    But you need to boot from another drive or DVD. Maybe install OS X to another drive (shrink volume so you have 30GB).
    Installing software in today's age of disk storage shouldn't require trashing files, unless you are working on old Raptor or small SSD.
    And instead of trash, move files to another drive, and always keep media files and libraries (not system libraries) off your system drive and onto a data drive.
    When in doubt, unsure what something is... don't!

  • MacBook Pro won't boot. Grey Screen appears, apple logo then nothing

    I'm very frustrated. I was using my laptop and suddenly the rainbow wheel appears and it freezes. I tried to hard reboot it and when it restarted a grey screen appears and the apple logo shows up. I bought it used from a Micro Center and I believe it's out of warranty. What is going on and what are my options?

    Take each of these steps that you haven't already tried. Stop when the problem is resolved.
    Step 1
    The first step in dealing with a boot failure is to secure your data. If you want to preserve the contents of the startup drive, and you don't already have at least one current backup, you must try to back up now, before you do anything else. It may or may not be possible. If you don't care about the data that has changed since your last backup, you can skip this step.   
    There are several ways to back up a Mac that is unable to boot. You need an external hard drive to hold the backup data.
         a. Boot into the Recovery partition, or from a local Time Machine backup volume (option key at startup.) When the OS X Utilities screen appears, launch Disk Utility and follow the instructions in this support article, under “Instructions for backing up to an external hard disk via Disk Utility.”
    b. If you have access to a working Mac, and both it and the non-working Mac have FireWire or Thunderbolt ports, boot the non-working Mac in target disk mode. Use the working Mac to copy the data to another drive. This technique won't work with USB, Ethernet, Wi-Fi, or Bluetooth.
    c. If the internal drive of the non-working Mac is user-replaceable, remove it and mount it in an external enclosure or drive dock. Use another Mac to copy the data.
    Step 2
    Sometimes a boot failure can be resolved by resetting the NVRAM.
    Step 3
    Press and hold the power button until the power shuts off. Disconnect all wired peripherals except those needed to boot, and remove all aftermarket expansion cards. Use a different keyboard and/or mouse, if those devices are wired. If you can boot now, one of the devices you disconnected, or a combination of them, is causing the problem. Finding out which one is a process of elimination.
    If you've booted from an external storage device, make sure that your internal boot volume is selected in the Startup Disk pane of System Preferences.
    Step 4
    Boot in safe mode. Note: If FileVault is enabled on some models, or if a firmware password is set, or if the boot volume is a software RAID, you can’t do this. Post for further instructions.
    Safe mode is much slower to boot and run than normal, and some things won’t work at all, including wireless networking on certain Macs.
    The login screen appears even if you usually log in automatically. You must know your login password in order to log in. If you’ve forgotten the password, you will need to reset it before you begin.
    When you boot in safe mode, it's normal to see a dark gray progress bar on a light gray background. If the progress bar gets stuck for more than a few minutes, or if the system shuts down automatically while the progress bar is displayed, your boot volume is corrupt and the drive is probably malfunctioning. In that case, go to Step 5.
    If you can boot and log in now, empty the Trash, and then open the Finder Info window on your boot volume ("Macintosh HD," unless you gave it a different name.) Check that you have at least 9 GB of available space, as shown in the window. If you don't, copy as many files as necessary to another volume (not another folder on the same volume) and delete the originals. Deletion isn't complete until you empty the Trash again. Do this until the available space is more than 9 GB. Then reboot as usual (i.e., not in safe mode.)
    If the boot process hangs again, the problem is likely caused by a third-party system modification that you installed. Post for further instructions.
    Step 5
    Launch Disk Utility in Recovery mode (see Step 1.) Select your startup volume, then run Repair Disk. If any problems are found, repeat until clear. If Disk Utility reports that the volume can't be repaired, the drive has malfunctioned and should be replaced. You might choose to tolerate one such malfunction in the life of the drive. In that case, erase the volume and restore from a backup. If the same thing ever happens again, replace the drive immediately.
    This is one of the rare situations in which you should also run Repair Permissions, ignoring the false warnings it may produce. Look for the line "Permissions repair complete" at the end of the output. Then reboot as usual.
    Step 6
    Reinstall the OS. If your Mac was upgraded from an older version of OS X, you’ll need the Apple ID and password you used to upgrade.
    Step 7
    Repeat Step 6, but this time erase the boot volume in Disk Utility before installing. The system should automatically reboot into the Setup Assistant. Follow the prompts to transfer your data from a Time Machine or other backup.
    Step 8
    This step applies only to older Macs (not current models) that have a logic-board ("PRAM") battery. Both desktop and portable Macs used to have such a battery. The logic-board battery is separate from the main battery of a portable. A dead logic-board battery can cause a boot failure. Typically the boot failure will be preceded by loss of the startup disk and system clock settings. See the user manual for replacement instructions. You may have to take the machine to a service provider to have the battery replaced.
    Step 9
    If you get this far, you're probably dealing with a hardware fault. Make a "Genius" appointment at an Apple Store to have the machine tested. If you can't get to an Apple Store, go to another authorized service provider.

Maybe you are looking for