Unexpected error when installing OS update in OS X I have gotten this error every time I have upgraded my OS since Mountain Lion (10.8 -> 10.8.1, 10.8.1 -> 10.8.2).

However after clicking the restart button on the error dialog and the computer has restarted, I have the newest version of the OS.

I can see this in the "About this Mac" dialog and that the App Store doesn't show any updates.

What is causing this and is there an error log where I can find details about this unexpected error?



Edit: Here is the errors I could find in install.log:


Oct  6 22:53:12 tyilos-macbook.home installd[83951]: kextcache: Link failed (error code 5).
Oct  6 22:53:12 tyilos-macbook.home installd[83951]: kextcache: Prelink failed for com.sierrawireless.driver.SierraDIPSupport; aborting prelink.
Oct  6 22:53:12 tyilos-macbook.home installd[83951]: kextcache: Failed to generate prelinked kernel.
Oct  6 22:53:12 tyilos-macbook.home installd[83951]: kextcache: Child process /usr/sbin/kextcache[83973] exited with status 71.
Oct  6 22:53:12 tyilos-macbook.home installd[83951]: kextcache: Error 107 rebuilding /System/Library/Caches/com.apple.kext.caches/Startup/kernelcache.
Oct  6 22:53:12 tyilos-macbook.home installd[83951]: PackageKit: releasing Spotlight indexing
Oct  6 22:53:12 tyilos-macbook.home install_monitor[83968]: Re-included: /Applications, /Library, /System, /bin, /private, /sbin, /usr
Oct  6 22:53:13 tyilos-macbook.home installd[83951]: PackageKit: releasing backupd
Oct  6 22:53:13 tyilos-macbook.home installd[83951]: PackageKit: allow user idle system sleep
Oct  6 22:53:13 tyilos-macbook.home installd[83951]: PackageKit: Install Failed: Error Domain=PKInstallErrorDomain Code=121 "An error occurred while updating system extension information." UserInfo=0x7fdc921d6c20 {NSUnderlyingError=0x7fdc90eb20f0 "The operation couldn’t be completed. (kextcache error 71.)", NSLocalizedDescription=An error occurred while updating system extension information., arguments=(
        "-update-volume",
        "/",
        "-Installer"
    )} {
        NSLocalizedDescription = "An error occurred while updating system extension information.";
        NSUnderlyingError = "Error Domain=kextcache Code=71 \"The operation couldn\U2019t be completed. (kextcache error 71.)\"";
        arguments =     (
            "-update-volume",
            "/",
            "-Installer"
        );
    }



Oct  6 22:53:13 tyilos-macbook.home Software Update[83950]: Error: An error occurred while updating system extension information. (PKInstallErrorDomain code 121)




Edit 2: Result of doing kextstat -kl | awk ' !/apple/ { print $6 $7 } ':


com.parallels.kext.prl_usb_connect(7.0
com.globaldelight.driver.BoomDevice(1.1)
com.manycamllc.driver.ManyCamDriver(0.0.9)
com.Cycling74.driver.Soundflower(1.6.2)
com.logmein.hamachi(1.0)
com.parallels.kext.prl_hypervisor(7.0
com.parallels.kext.prl_hid_hook(7.0
com.parallels.kext.prl_netbridge(7.0
com.parallels.kext.prl_vnic(7.0
org.virtualbox.kext.VBoxDrv(4.1.18)
org.virtualbox.kext.VBoxUSB(4.1.18)
org.virtualbox.kext.VBoxNetFlt(4.1.18)
org.virtualbox.kext.VBoxNetAdp(4.1.18)
The Console.app found in the Application -> Utilities folder (or Other folder in Launchpad)  gives you access to the logs for the machine.

Under /var/log, the file named install.log (and any variants named install.log.x.bz2) will give you the information about the last install.

Note the files named install.log.x.bz2  are older versions of the same file created duting a process called rolled over when the file size of the current install.log file reaches 1000K

You need to search your install.log for the string "OSXUpd10.8.2Supp.pkg" which will give you an idea of what happened during your install.

Update: From your log file, it would appear that your have a Kernel Extension that is causing this issue.  Either it has a permissions problem, or is somehow causing this annoying issue.

can you paste this line into Terminal, and post the results?

kextstat -kl | awk ' !/apple/ { print $6 $7 } '


Update 2: This would appear to be at least a trial and error solution. There are multiple threads on the Apple Support forums, from installing 10.8.2 to installing Xcode.  Each one has different people each having issues with different kernel extensions that when removed resolved their issues.

I'm afraid I don't have any way to determine which of your kernel extensions is the cause; someone else may be able to shed more light.  I would however expect the Virtual Box and Parallels extensions to be fine, not the least since I have them both also, but that this issue would be more widespread if they were the issue.

Finally: the manual for kextcache advises that using the touch command on /System/Library/Extensions/ forces the kext cache to be rebuilt.  You could use this as a method to determine which kext is causing the issue by uninstaling each in turn, performing the cache update and checking the logs to see if the cache was updated successfully.