Jailbreak your iPhone

How to Back up & Restore Your Kexts Before OSX86 Upgrades.


Kexts, or kernel extensions are drivers that are installed to /System/Library/Extensions/.Kext files often have kext the “.kext” extension and allow for extra hardware support and and in the case of OSx86, to replace Appleʼs original drivers with ones that are optimized for use on PCs. Leopard holds kext files/folders in the /System/Library/Extensions folder, at boot time the relevant kext are uploaded from Extensions.mkext this is a cache folder that contains kext related to the installed hardware. If you loves your hackintosh then take a full backup of your kexts because some kexts may disappear after the update procedure.


For making backup of your Kexts open Terminal and type in these commands:

sudo -s
[enter password]
cp -r /System/Library/Extensions /System/Library/Extensions.backup
cp -r /mach_kernel /mach_kernel.backup

For restoring your Kexts open Terminal and type in these commands:

sudo -s
[enter password]
cp -r /System/Library/Extensions.backup /System/Library/Extensions
cp -r /mach_kernel.backup /mach_kernel


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Comments ( 10 )

Have Something To Say ?

  1. Daneil January 5, 2011 Reply

    Well, you can insert your original hackintosh DVD and then let it boot. then go to terminal and write those right?

  2. lownly March 29, 2010 Reply

    Please help me
    when i try to run these commands :
    sudo -s
    (my password)
    cp -R /mach_kernel.backup /mach_kernel

    i get the following message :
    cp: /mach_kernel: Permission denied

  3. mane January 28, 2010 Reply

    Help, is there anyboy out there how has a hint for me?
    If I start me hack, the mouse dont move and the keybord does not work (USB).
    Best mane

  4. anmol January 7, 2010 Reply

    Does anyone have a copy of the vanilla SL 10.6 or 10.6.1 extensions ?
    I tried different things to get stuff to work on my netbook, now I have mesed things up–
    Wish I had backed up my extensions 🙁

  5. BL3SSED1 November 20, 2009 Reply

    Hi, I’m using iPC 10.5.6 when I upgrade to 10.5.7 or 10.5.8 the video no longer works. How can I use this backup and restore method to restore the .kext that was installed during the original install (before the upgrade) I’m using use the intel 915GMA chipset.

  6. Alex July 12, 2009 Reply

    Missing something very important here… the steps or an alternate procedure to boot the OS without crashing so you can, then, restore the darn kexts…

  7. Robert June 27, 2009 Reply

    Anthony, your getting that because you must have forgotten the first part sudo -s

    hope that helps

  8. Anthony June 20, 2009 Reply

    Why do I get the following when trying to run this command ?

    cp: /system/library/extensions.backup: Permission denied
    cp: /system/library/extensions: unable to copy extended attributes to /system/library/extensions.backup: Permission denied

  9. Vinay Prashar May 22, 2009 Reply

    @ Madoc1 the kexts will be backuped in mach_kernel.backup file you can’t access it bcause it is a system file but you can restore it again by typing the second command given in the post above.

  10. madoc1 May 22, 2009 Reply

    where the ktext are saved?

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