When i on my Mac pro there is a folder sign with question mark?

sir when i on my Pac Pro there is appear a folder sign with question mark in white screen .what is the problem tell me pls?

http://support.apple.com/kb/ts2570

Similar Messages

  • Mac Book just displays a folder icon with question mark

    Hi! My mac does not turn on, it just displays a folder with a question mark. What should I do?
    Btw, I've just turned it on in a country with a lower power supply, can this be the problem? I'm kind of desperate by now.
    Thank you. [email protected]

    Carla
    Welcome to the forums here. You might also want to check out Mac Forums they're great too The credits are secondary, just want to be able to help if I can. I'm sorry the hardware test did not start for you. I know sometimes reading the forums and seeing other issues may cause one to worry, it worries me too, but if this is your first issue with your MB don't have any worries. I'm pretty sure your warranty will apply. If have any problems with that and can call a toll free number to the states 800-275-2273. Here's a link with Apple numbers.
    Joseph

  • Hi. My Macbook Pro won't start, in the middle of the screen, there is a folder sign with a question mark blinking. Thanks a lot!

    Hi. My Macbook Pro won't start, in the middle of the screen, there is a folder sign with a question mark blinking. Thanks a lot!

    Here's a link to a Support page on the topic, which may be of help in finding resolution:
    •A flashing question mark or globe appears when you start your Mac
    There are a few known causes of this symptom, so you'd have to try some things to
    see if you can narrow down the cause; this often accomplished by finding success.
    Hopefully the info there helps.
    Good luck & happy computing!

  • Hi . i have Intel based iMac. i erased whole hard disk. now it flashes folder icon with question mark... i have no internet or orginal dvd.... i want to clean install any mac osx..friend got mac book pro and osx in dmg format . what are my options?

    hi . i have Intel based iMac. i erased whole hard disk. now it flashes folder icon with question mark... i have no internet or orginal dvd.... i want to clean install any mac osx..friend got mac book pro and osx in dmg format . what are my options?

    On your friend's computer with an internet connection, log into the Mac App Store with your ID and download Yosemite from the Purchases section of the Mac App Store. The make a bootable USB install media using
    http://liondiskmaker.com/
    Then boot from that on your computer and install
    You need an internet connection to install via Recovery mode

  • I got new hard driver for my MacBook I don't have the cd but I do have flash drive that has the software I need help because when I turn on my laptop it shows me a file with question mark how can I install the software from the flash driver?

    I got new hard driver for my MacBook I don't have the cd but I do have flash drive that has the software I need help because when I turn on my laptop it shows me a file with question mark how can I install the software from the flash driver?

    Hold down the Option key while you boot your Mac. Then, it should show you a selection of devices. Click your flash drive and it will boot from that.

  • Mac Pro not detecting internal HD. Blinking Question Mark!!

    Hi there,
    Ive been looking for an answer about my problem but it seems most of the people has got the problem; the hard drive might be damaged. Thats not my case.
    Ive got two Mac Pros. One is working flawlessly. So I swaped HDs to see what happened and when I turned on the computer, the good MAC detected the hard drive of the failing computer and I logged in normally. When I turned on the failing computer with the good HD, it didnt read it. In conclusion I realized that there was not a HD problem, something else is going on.
    After that, using the good Mac PRo, I installed both HDs and both were detected. This confirmed that definitely, the HDs are Ok. Whats wrong?? I dont know, hope you people can help me.
    Thanks a lot.

    The blinking question mark says you could not find:
    The preferred System
    of the preferred version
    on the preferred drive.
    All these parameters are stored in Parameter RAM, and sometimes they get damaged "just because".
    If you use
    System Preferences > Startup Disk ...
    ... to set the correct startup disk again. your problems may be over.
    If not, you may need to reset the PRAM.
    If that does not solve the problem in the long run, you may need to replace the PRAM backup battery.

  • TS3423 17" macbook pro won't start blue file with question mark is all that appears on the screen

    My old macbook pro will not start up. Worked fine yesterday, today all I gat is the startup sound and a blank blue screen. After a while the screen shows a file folder icon with a question mark in it. Any ideas

    Question (?) Mark, Blinking Folder, or Gray Screen at Startup
    These are related but not identical issues. Their causes are outlined in Intel-based Mac- Startup sequence and error codes, symbols. Solutions may be found in:
    A flashing question mark appears when you start your Mac
    Mac OS X- Gray screen appears during startup
    In most cases the problems may be caused by:
    Problem with the computer's PRAM - See Resetting your Mac's PRAM and NVRAM.
    Boot drive's directory has been corrupted - Repair with Disk Utility.
    Critical system files are damaged or deleted - Reinstall OS X.
    The disk drive is physically non-functional - Replace the hard drive.
    Repair the Hard Drive and Permissions
    Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
    If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
    The main difference if you are using Lion or Mountain Lion is that you must first boot from the Recovery HD:
    Boot From The Recovery HD:
    Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
    Reinstall Snow Leopard Without Erasing The drive
    1. Repair the Hard Drive and Permissions
    Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
    If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
    2. Reinstall Snow Leopard
    If the drive is OK then quit DU and return to the installer.  Proceed with reinstalling OS X.  Note that the Snow Leopard installer will not erase your drive or disturb your files.  After installing a fresh copy of OS X the installer will move your Home folder, third-party applications, support items, and network preferences into the newly installed system.
    Download and install Mac OS X 10.6.8 Update Combo v1.1.
    Reinstalling Lion/Mountain Lion Without Erasing The Drive
    Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
    Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the main menu. Repair the Hard Drive and Permissions as follows.
    When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu.
    Reinstall Lion/Mountain Lion: Select Reinstall Lion/Mountain Lion and click on the Continue button.
    Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.

  • Help ! Flashing folder icon with question mark when starting up

    Hi, I have tried to restore my macbook pro 15 (2012 model with Yosemite OS  X) to factory settings and wipe out the hard drive but on restarting it I now just get a blank screen with a flashing folder icon with a question mark on it. Any help/advice anyone I would be very grateful for ! Thanks,  Mark

    Something didn't install properly.
    Try these in order testing your system after each to see if it's back to normal:
    1. a. Resetting your Mac's PRAM and NVRAM
        b. Intel-based Macs: Resetting the System Management Controller (SMC)
    2. Restart the computer in Safe Mode, then restart again, normally. If this doesn't help, then:
         Boot to the Recovery HD: Restart the computer and after the chime press and hold down the
         COMMAND and R keys until the Utilities menu screen appears. Alternatively, restart the
         computer and after the chime press and hold down the OPTION key until the boot manager
         screen appears. Select the Recovery HD and click on the downward pointing arrow button.
    3. Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the Utilities menu. Repair the Hard Drive and Permissions as follows.
    When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu. Select Restart from the Apple menu.
    4. Reinstall Yosemite: Reboot from the Recovery HD. Select Reinstall OS X from the Utilities menu, and click on the Continue button.
    Note: You will need an active Internet connection. I suggest using Ethernet if possible
                because it is three times faster than wireless.
    5. Reinstall Yosemite from Scratch:
    Be sure you backup your files to an external drive or second internal drive because the following procedure will remove everything from the hard drive.
    How to Clean Install OS X Yosemite
    Note: You will need an active Internet connection. I suggest using Ethernet if possible
                because it is three times faster than wireless.

  • Mid 2009 Macbook Pro boots with folder icon with question mark

    I was on OS X Mavericks when it was working.
    Alright, so I was having issues with my hard drive. I tried recovering it, repairing it, and nothing would work. So I have another hard drive already formatted to fat32, I pluged it in and turn on the macbook and it comes up with a grey screen with blinking folder icon. I then tried plugging it the old hard drive and its doing the same thing. I plugged the new hard drive back in and held the option key on startup and all it did was goto a grey screen with the cursur, and thats it. I tried option + command key and it just goes to the blinking folder icon. I tried command + r, holding shift, all lead back to the blinking folder or blank grey screen with the cursur. I don't know what else I could do? Any help is appreciated.

    There seem to be forum system operations problems.  I tried to send this earlier:
    badluckkyle wrote
    Is there anyway to make a bootable external HDD on a windows computer? Thats all I have right now.
    No.  Not on a PC.
    Two things you can try.  Take the original HDD, put it in an enclosure, and connect it to the MBP via USB (or Firewire).  Start the MBP with the OPTION key down.  If display shows the external HDD, click on it.  See if it boots the MBP.
    Second option is to connect the new HDD to the MBP.  Get the original installation disk and put it into the drive and start the MBP with the C key held down.  Start the installation process and when you get to the dispaly where there is a menu bar, click on UTILITIES.  From the drop down menu, select Disk Utility.  Select Disk Utility>Erase and format the HDD to Mac OS Extended (Journaled).  Complete the OSX installation.
    That then will be a boot drive.  It should be able to boot the MBP externally and internally (unless the internal SATA cable is faulty).
    If your original OSX was Leopard and you have a Snow Leopard disk, install Snow Leopard.  Then run software update so that you have 10.6.8 installed.  If you want Mavericks, then you can install that.
    Ciao.
    badluckkyle wrote:
    Will it boot from an external on its own if I cant boot into anything? If so I can only put OS X on my external if formatted as exFat, files too big to copy to fat 32.
    As indicated above, if the boot drive is functional, it should be able to boot your MBP from an enclosure.
    You can only install an Apple OSX on a HDD formatted Mac OS Extended (Journaled).  NO other format will accept a Mac OSX.
    Ciao.

  • TS1440 When booting up, grey screen with a 'folder icon' with 'question mark' flashes?

    When I boot up, a grey screen appears with a folder icon with a question mark inside it. The Mac won't respond to and commands or anything, only the On/Off Power button.
    Any ideas? If you read my previous question, you can see what happened before all of this started happening.
    Thanks,
    -Dylan

    Did you follow this procedure?
    http://www.dummies.com/how-to/content/how-to-install-or-reinstall-mac-os-x-mount ain-lion.html

  • On start up my mac is showing a folder and flashing question mark sign?

    On start up my mac shows a folder sign & flashing question mark?? Help and Why??

    Question (?) Mark, Blinking Folder, or Gray Screen at Startup
    These are related but not identical issues. Their causes are outlined in Intel-based Mac- Startup sequence and error codes, symbols. Solutions may be found in:
    A flashing question mark appears when you start your Mac
    Mac OS X- Gray screen appears during startup
    In most cases the problems may be caused by:
    Problem with the computer's PRAM - See Resetting your Mac's PRAM and NVRAM.
    Boot drive's directory has been corrupted - Repair with Disk Utility.
    Critical system files are damaged or deleted - Reinstall OS X.
    The disk drive is physically non-functional - Replace the hard drive.
    Repair the Hard Drive and Permissions
    Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
    If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
    The main difference if you are using Lion or Mountain Lion is that you must first boot from the Recovery HD:
    Boot From The Recovery HD:
    Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
    Reinstall Snow Leopard Without Erasing The drive
    1. Repair the Hard Drive and Permissions
    Boot from your Snow Leopard Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
    If DU reports errors it cannot fix, then you will need Disk Warrior and/or Tech Tool Pro to repair the drive. If you don't have either of them or if neither of them can fix the drive, then you will need to reformat the drive and reinstall OS X.
    2. Reinstall Snow Leopard
    If the drive is OK then quit DU and return to the installer.  Proceed with reinstalling OS X.  Note that the Snow Leopard installer will not erase your drive or disturb your files.  After installing a fresh copy of OS X the installer will move your Home folder, third-party applications, support items, and network preferences into the newly installed system.
    Download and install Mac OS X 10.6.8 Update Combo v1.1.
    Reinstalling Lion/Mountain Lion Without Erasing The Drive
    Boot to the Recovery HD: Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
    Repair the Hard Drive and Permissions: Upon startup select Disk Utility from the main menu. Repair the Hard Drive and Permissions as follows.
    When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list.  In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive.  If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu.
    Reinstall Lion/Mountain Lion: Select Reinstall Lion/Mountain Lion and click on the Continue button.
    Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.

  • Even when I charge my Mac Pro to the full bar, the battery seems to be drained even when I am not using it. Example, after charging it full, i switched it on the next day and its 79% battery left. Is there something wrong? help please

    Even when I charge my Mac Pro to the full bar, the battery seems to be drained even when I am not using it. Example, after charging it full, i switched it on the next day and its 79% battery left. Is there something wrong? help please

    Assuming you are disconnecting from line power, when you say switched on, do you mean it was shutdown or in sleep mode?  If sleep mode the battery will still drain because sleep still keeps some things active and the battery does drain a little.  However, to go from 100% to 79% charge overnight is a bit excessive in sleep mode.  Unless you have some processes set to activate over night by the cron file and do things like backup the system.
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  • Hello ...  I have a problem with a wifi connection speed on my mac pro ... the problem is that in one room the internet opening for the websites is extremely slow ... but when i move the mac pro somewhat to other location ... the internet speed increase

    hello ....
    my connection problem on my mac pro is :
    that when i try to open a website on safari .... it delays ... and takes more than 30 seconds to open completely ...
    but when i move the mac pro to another location ... its internet opening speeds up ....
    also in one room ... web opening delays .... but on other rooms it is normal
    so what can i do to solve this problem ....
    Note : also when i hold it up and move in the same room ... the speed changes and somewhere speed up ... and in another location speed down ..
    thanks for you all ...
    Waiting for your support ... as quick as possible ...

    WiFi signals get stronger the closer the machine is to the router and the less interference/blocking of the signal like via walls with metal in them or of thick concrete.
    Since the signal emanates outwards in a sphere, your supposed to place the wireless router in a central location in the building so it covers all areas.
    The power of the router also has a affect, if your router is old or something not that powerful like a Airport Express, it doesn't have the ability to filter out other signals or enough punch to get through walls etc. or cover a large area as effectively.
    If you buy/have a powerful router of newer make and have issues where there is metal in the walls or thick concrete, then you can buy something like OpenMesh and by using Ethernet cables from the back of the router, extend the WiFi signal into other rooms and areas past the blockage.
    https://www.open-mesh.com/

  • I replaced the battery on my RAID card, when I booted my mac pro up, I get the folder with the question mark. I used a boot USB drive to boot and when I looked in the RAID utility, my RAID 5 volumes were no longer showing, advise.

    I replaced the battery on my RAID card, when I booted my mac pro up, I get the folder with the question mark. I used a boot USB drive to boot and when I looked in the RAID utility, my RAID 5 volumes were no longer showing, advise.
    Ernest

    Not sure if I'm following you. I have 4 hard drives installed on my Mac Pro. I had a RAID 5 configured and functional for about 5 months. My battery died on the RAID card. I replaced the battery, seated the RAID card back in the slot I removed it from. When I booted to the USB drive to look in the RAID utility, I could see the battery is charged but my volumes are not showing.
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  • When i active my mac pro all i get is a white screen and  it loading .. and when it fully loaded it turns off and the same thing keep on happening again

    when i active my mac pro all i get is a white screen and  it loading and when it fully load its turn off , and it keep on doing the same thing for hours

    Hi Shahenaz,
    It's a little difficult to understand exactly what's going on with your mac based on the description you gave. Is there anything else you could add? Is it stuck in a reboot loop? Or is it just showing a white screen forever?
    I had pretty much the same problem a few days ago, and was worried my mac was screwed permanently, but I got it fixed up no problem!
    Follow these steps to try and troubleshoot/fix the problem.
    1. Boot into OSX Recovery Mode
    First, turn off your Mac. If it isn't responding, or is stuck in a reboot loop, just hold down the power button until it turns off, and you hear the fans stop. Then boot it while holding the Command and R keys. If it successfully boots into OSX Recovery Mode, continue with this step. If not, skip to step two. (My Mac couldn't successfully boot into the recovery mode, so I had to go to step 2)
    Select "Disk Utility" from the list of options, and find your built in hard drive from the list on the left. Usually there are two listings/names for your drive. The first should be something like "500GB longchainoflettersnumbers Media". Then the one below will be a little easier on the eyes, named Macintosh HD, if you haven't changed its name. That's the one you want, click it.
    Now go to the "First Aid" tab. Click on the "Verify Disk" button in the bottom right corner, and let it do its thing. Once that's done, hit repair disk, also in the bottom right corner. If your disk is corrupted, you may need to run the repair process several times, before it comes up completely clean.
    Once this is done, select Shut Down from the Apple menu and, once your Mac is completely off, turn it back on like normal. If it works, great. If not, proceed to step two.
    2. SafeBoot
    Sometimes, when a mac is acting up and doesn't want to start, all it takes is a safe boot, followed by a regular restart. Or maybe you recently installed a program that either has malicious or errored coding that's causing your troubles. This is where Safe Boot comes in.
    Turn off your mac, and reboot it while holding Shift. (If you want to see the process that's going on in the background, boot while holding Shift, Command, and V. This will enter something called Verbose Mode).
    If it boots successfully into Safe Mode, great. If you believe that there's a particular program that you recently downloaded that might be causing your trouble, now's the time to delete it. If not, just reboot normally and see if it works! If it doesn't, or if your Mac didn't even Safe Boot like mine, proceed to step 3.
    3. Fsck!
    For this step, you're going to be booting your mac into Single User Mode. I'm not going to go into details as to what this step does, but it works for some people. Here are the steps.
    Turn off your mac, and reboot it while holding Command and S. The screen should go black, and you'll see some white text run across the screen, wait a few seconds, until you see the command prompt. Now type
    fsck -fy
    and hit the Enter key. This will run a series of system checks, which could take a few minutes. Be patient on this part. Once it's done, it will show one of two messages:
    1. "The volume (your Mac) appears to be OK
    or
    2. "File System Was Modified"
    If you got message 1, type reboot and press Return. Hopefully your computer works after this - if not, proceed to step 4.
    If you got message 2, run the same command again until you get message 1. If it doesn't seem to be working, turn off your system and proceed to step 4.
    If you couldn't even boot into Single User Mode in the first place (like me), go to step 4 anyways.
    Step 4: Reset the NVRAM
    The NVRAM is another kind of RAM that stores data like the computer volume you had set before you turned it off, or the screen brightness, resolution etc. This memory is saved, unlike with regular RAM. Resetting it isn't harmful to your system, it will just put your screen brightness, volume, etc. to defaults.
    Turn off your Mac, and reboot while holding Command, Option, P, and R, and continue holding them down until you hear the computer restart again.
    I can't really explain why to do this step, I just know it works for some people, and seems to be what unbricked my MacBook Pro. If none of these steps, fixed your Mac, well the situation is looking pretty grim. Try setting up a meeting with a Mac Genius at your local Apple store. However, I know that many other people with these symptoms ended up having a logic board failure. Apple can swap out your logic board for a new one, but the price is pretty hefty, somewhere around $300 I believe.
    Well I wish you luck, I hope this helped you!

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