DaveWaldorf

Q: Deleted system Extensions

I searched kernell in the system exstensions and deleted all of them. After restarting, loading doesn't finish and stay in the middle and don't move. I can use my Macbook, but I really have to fix it ASAP. I'm getting crazy cause don't know what to do

MacBook Pro, OS X Yosemite (10.10.5), null

Posted on Sep 10, 2015 4:53 PM

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Q: Deleted system Extensions

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  • by Niel,

    Niel Niel Sep 10, 2015 4:54 PM in response to DaveWaldorf
    Level 10 (312,963 points)
    Mac OS X
    Sep 10, 2015 4:54 PM in response to DaveWaldorf

    Restart with the Command and R keys held down, and reinstall Mac OS X.

     

    (133137)

  • by Kappy,Apple recommended

    Kappy Kappy Sep 10, 2015 4:54 PM in response to DaveWaldorf
    Level 10 (271,184 points)
    Desktops
    Sep 10, 2015 4:54 PM in response to DaveWaldorf

    Reinstalling OS X 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.

     

    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 and press the Continue button. After Disk Utility loads select the indented Macintosh HD entry from the the left side list.  Click on the First Aid tab, then click on the Repair Disk button. If Disk Utility 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 Disk Utility and return to the main menu.

     

    Reinstall OS X: Select Reinstall OS X 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 and more reliable.

     

    Alternatively, see:

     

    Reinstall OS X Without Erasing the Drive

     

    Choose the version you have installed now:

     

    OS X Yosemite- Reinstall OS X

    OS X Mavericks- Reinstall OS X

    OS X Mountain Lion- Reinstall OS X

    OS X Lion- Reinstall Mac OS X

     

         Note: You will need an active Internet connection. I suggest using Ethernet

                     if possible because it is three times faster than wireless.

  • by DaveWaldorf,

    DaveWaldorf DaveWaldorf Sep 11, 2015 2:40 AM in response to Kappy
    Level 1 (0 points)
    Sep 11, 2015 2:40 AM in response to Kappy

    During repairing the disk It shows the same after every time "Unable to unmount volume for repair" .

     

    also I can't reinstall the OS X. I tried a few time but it shows the same "Downloading failed try from the purchase tab" something like this after a few hours of downloading. What to do?

     

     

  • by Kappy,Apple recommended

    Kappy Kappy Sep 11, 2015 12:49 PM in response to DaveWaldorf
    Level 10 (271,184 points)
    Desktops
    Sep 11, 2015 12:49 PM in response to DaveWaldorf

    Did you try this from the Recovery HD? You cannot repair the active startup volume. Try this: Shutdown the computer completely. Wait about five or ten minutes. Then reboot to the Recovery HD again and see if you can repair the OS X volume. If you cannot, then do you have boot DVDs that came with the computer when it was new? If so, then use that to startup the computer, open Disk Utility and repair the drive. If the computer is from 2010 or earlier then there will be software restores discs that came with it. If you have the new 2015 MacBook, then do this:

     

    Install OS X Using Internet Recovery

     

    Be sure you backup your files to an external drive or second internal drive, if you can, because the following procedure will remove everything from the hard drive.

     

    Boot to the Internet Recovery HD:

     

    Restart the computer and after the chime press and hold down the COMMAND-OPTION- R keys until a globe appears on the screen. Wait patiently - 15-20 minutes - until the Recovery main menu appears.

     

    Partition and Format the hard drive:

     

    1. Select Disk Utility from the main menu and click on the Continue button.
    2. After DU loads select your newly installed hard drive (this is the out-dented entry with the mfgr.'s ID and size) from the left side list. Click on the Partition tab in the DU main window.
    3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Click on the Options button, set the partition scheme to GUID then click on the OK button. Set the format type to Mac OS Extended (Journaled.) Click on the Partition button and wait until the process has completed. Quit DU and return to the main menu.

     

    Reinstall OS X: Select Reinstall OS X and click on the Install button. Be sure to select the correct drive to use if you have more than one.

     

    Note: You will need an active Internet connection. I suggest using Ethernet if possible because it is three times faster than wireless.

     

    This should restore the version of OS X originally pre-installed on the computer.