System extensions can't be used

After a major freeze I managed to restart using the install disk and did a major cleanup. But I can't print anything -- and suspect a problem with one of the automatic updates from Mac involving the printer drivers. I keep on getting notices re 25 system extensions that can't be used -- nearly all have got .ktext on the end. How do I find them, and should I uninstall / reinstall? If so, where do I get them from?

In Finder, do these files show in /System/Library/Extensions ?
& from Finder, what exactly happens when you attempt to remove them ? (you should get a prompt asking for an admin name/pass). If not, select one & see what the sharing/permissions section of Finder - File - Get Info looks like...
If you use an hp printer, I'd (re)install the update.

Similar Messages

System Extension can not be used

I have recently updated iTunes to the latest version. During the installation, a pop-up error message appeared saying "The system extension "System/Library/Extensions/AppleUSBEthernetHost.Kext" was installed improperly and cannot be used. Please reinstalling it, or contact the product's vendor for an update".
I have tried to reinstall iTunes, but no help. What could this issue and what is the fix ??

Open Terminal in the Utilities folder. Paste the following at the prompt:
sudo chown -R root:wheel System/Library/Extensions/AppleUSBEthernetHost.Kext
Press RETURN. Enter your admin password when prompted. It will not echo to the screen so type carefully. Press RETURN again.
Restart the computer.

REceiving error - system extension missing / cannot be used

Hello,
Posting here because I see this error frequently when doing updates. I received and performed a system update for iTunes yesterday and received the following twice:
System extension cannot be used
The system extension "/System/Library/Extensions/CNQL3202_ClassicNotSeize.kext" was installed improperly and cannot be used. Please try reinstalling it, or contact the product's vendor for an update.
I see these frequently when performing updates so I suspect it's not iTunes specific. What is the missing file and where can I find it / what can I do to eliminate the error?
Thanks much in advance.
E.

It sounds like you made a permissions change that you extended to the entire drive, thus making all extensions unusable.
Start by doing the following:
Repair the Hard Drive and Permissions
Boot from your OS X 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. Now restart normally.
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.
This will most likely take considerable time because DU will need to fix permissions on every system file affected and there are tens of thousands of files. Perhaps with any luck this will fix the problem although no guarantees. I hope you have a backup of the previous system before you made the permissions changes.

Firefox 5 won't work with Mac OS 10.4, but I can't afford to upgrade the system; how can I keep using Firefox 4?

This computer is an eMac running the Tiger operating system. Rather than upgrading the entire system, which is costly and time-consuming, is there simply a way to keep using the previous version of Firefox?

Firefox 3.6.28 is the latest version of Firefox that works on 10.4. [[Firefox no longer works with Mac OS X 10.4 or PowerPC processors]] You unfortunately have a PPC processor, so the only way you can use modern software is to purchase a new PC. Or, you can try using [http://www.floodgap.com/software/tenfourfox/ http://www.floodgap.com/software/tenfourfox/]. But please note that you will be using a community project that may or may not work.

System Extension Cant be used...ioplatform.kext

My Macbook keeps telling me the ioplatform system extension can't be used and needs reinstalling. Its a .kext file and it doesn't really disallow me from doing anything but it pops up frequently.
I have a Macbook Pro 15 with retina 2.5 GHz 16BG RAM and a 750M GCard and 512 SSD

If you don't already have a current backup, back up all data, then reinstall the OS.* You don't need to erase the startup volume, and you won't need the backup unless something goes wrong. If the system was upgraded from an older version of OS X, you may need the Apple ID and password you used.
If you use FileVault 2, then before running the Installer you must launch Disk Utility and select the icon of the FileVault startup volume ("Macintosh HD," unless you gave it a different name.) It will be nested below another icon with the same name. Click the Unlock button in the toolbar and enter your login password when prompted. Then quit Disk Utility to be returned to the main Recovery screen.
There are ways to back up a computer that isn't fully functional. Ask if you need guidance.
If you installed the Java runtime distributed by Apple and still need it, you'll have to reinstall it. The same goes for Xcode. All other data will be preserved.
*The linked support article refers to OS X 10.10 ("Yosemite"), but the procedure is the same for OS X 10.7 ("Lion") and later.

Can JMSPriority be used to distinguish between real-time, near real-time workloads?

IHAC that needs to throttle work passed to a backend system, i.e. limit
          the # of concurrent requests, as well as prioritize between different
          kinds of workloads including real-time, deferred real-time
          (asynchronous) and batch.
          I'm proposing to use a pool of MDBs reading of a single JMS queue. The
          max-free-beans-in-pool would be used to limit the concurrent access to
          the backend system.
          Can JMSPriority be used to distinguish between the different kinds of
          workloads? (real-time, near real-time and batch)
          How is the JMSPriority used when consuming messages from a queue in WLS
          JMS? Are messages dequeued in strict priority order or is there an
          algorithm to ensure lower priority messages are periodically consumed,
          i.e. to ensure they are not starved-out? Or do you have to create a
          message selector to dequeue based on priority?
          Is the an appropriate use of JMSPriority or should I set-up dedicated
          JMS queues for each of the different workload types?
          Cheers
          Simon


          Tom,
          How do you create custome connection factories in JMS? And also how can u
          change the MessageMaximum to 0? I thought the minimum is 1 and that u can only
          change in the config.xml file??
          Any code snippets on how to write custom connection factories would be helpful.
          Thank You,
          Sankas
          Tom Barnes <[email protected]> wrote:
          >Hi Simon,
          >
          >Answers in-line.
          >
          >Simon Pearce wrote:
          >
          >> IHAC that needs to throttle work passed to a backend system, i.e. limit
          >> the # of concurrent requests, as well as prioritize between different
          >> kinds of workloads including real-time, deferred real-time
          >> (asynchronous) and batch.
          >>
          >> I'm proposing to use a pool of MDBs reading of a single JMS queue.
          >The
          >> max-free-beans-in-pool would be used to limit the concurrent access
          >to
          >> the backend system.
          >>
          >> Can JMSPriority be used to distinguish between the different kinds
          >of
          >> workloads? (real-time, near real-time and batch)
          >>
          >> How is the JMSPriority used when consuming messages from a queue in
          >WLS
          >> JMS? Are messages dequeued in strict priority order or is there an
          >> algorithm to ensure lower priority messages are periodically consumed,
          >> i.e. to ensure they are not starved-out?
          >
          >To get priority sorting you must configure the destination to sort by
          >priority.
          >It sorts FIFO by default.
          >
          >In addition, you may want to tune-down the pipe-line size between
          >the JMS server and the MDB (create a custom connection factory, and
          >set MessagesMaximum to 0, default is 10), as the pipe-line is unsorted
          >and consequently messages will not "jump ahead" of each-other in the
          >pipe-line.
          >
          >> Or do you have to create a
          >> message selector to dequeue based on priority?
          >
          >No.
          >
          >>
          >>
          >> Is the an appropriate use of JMSPriority or should I set-up dedicated
          >> JMS queues for each of the different workload types?
          >
          >The latter, as long the app can tolerate concurrent execution of all
          >workload
          >types due to having an MDB per queue. The latter will perform better
          >than selectors,
          >and you won't have to worry about the unsorted pipe-line.
          >
          >>
          >>
          >>
          >> Cheers
          >>
          >> Simon
          >
          >Tom, BEA
          >

My system sometime can't boot

My computer can not restart. I have the system as below:
1) AMD Athlon XP 15000+ (NOT over clock) default CPU Volt: 1.71V
2) 512 MB PC133 Kingston Value Ram (Double side with 8 chips per side)
3) 300 watt Enlight Power Supply
4) 40 GB 5400 Rpm Maxtor HDD
5) 40*12*48 Aopen CD-RW Drive
6) OS – Windows XP Professional + Service Pack 1
7) VIA Service Pack 4.43
I upgrade my system with change of main board to MSI K7T Turbo2 (Bios version- 3.5 & date- 07/01/02)
and MSI MS-8852 Geforce 2 MX400 Card (64MB).
Before the upgrade ,the system runs perfectly ,after the upgrade and installation of programs ,the system sometimes can not rebooted using “ restart ” command through windows program. However it can booted using reset button. Unplug the reset button ,also same .
I would be much obligrd of you give me some suggestion to solve this problem.
Thanks!!!!!!!!!!!!!!!!!!!!!!

Hi,
When you replace a motherboard it's recommended you install Windows again from scratch.
Have you done this?

System extension cannot be used --can anyone help ?

so i spotted that the system library as well as the home library had permissions blocked for the administrator, so i unlocked all enclosed items permissions.
i already had issues being brought to senior advisor attention over 1,5 years now, about hangs and freezes. mostly hangs.
no one so far has been able to fix them.
well now spotting these warnings, after i allowed all permissions inside both libraries, have warnings show up.
i gather these are not prepperly installed softwares, but i cant figure out what softwares they could be, so i can take care of it.
so 4 warnings shows up :
System extension cannot be used
The system extension “/System/Library/Extensions/System.kext/PlugIns/Unsupported.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.
System extension cannot be used
The system extension “/System/Library/Extensions/System.kext/PlugIns/Private.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.
System extension cannot be used
The system extension “/System/Library/Extensions/IOPCIFamily.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.
System extension cannot be used
The system extension “/System/Library/Extensions/IOUSBFamily.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.

There isn't an "administrator" so who did you add and what permissions did you set.
In Get Info, they should be
system read & write
wheel read Only
everyone read only
The posix permissions, owner, and group should be
rwxr-xr-x root wheel
with ACE "group:everyone deny delete"
You may be able to recover by repairing permissions in Disk Utility, but you may have to reinstall the OS.

How do I reinstall a "System/Library /Extension CNQL123_ClassicNotSize.kext"that was improperly installed and can not be used? It is causing iTunes to crash

I instaled the latest Safari Update and iTunes Update and now when I select Podcasts it crashes iTunes--it seems to only be the Podcast option that causes the crash. So how do i install or reinstall the system extension listed above, that cannot be used? The error message suggest that I reinstall or contact the vendor????? I also added an app to my dashboard which I have delected. Should I reinstall the system that came with the mini ---Leopard 10.6.2?

If it has an uninstaller use that. Be sure you delete the kext file; and you will need to restart afterwards.
If there is no uninstaller then see the following:
Uninstalling Software: The Basics
Most OS X applications are completely self-contained "packages" that can be uninstalled by simply dragging the application to the Trash. Applications may create preference files that are stored in the /Home/Library/Preferences/ folder. Although they do nothing once you delete the associated application, they do take up some disk space. If you want you can look for them in the above location and delete them, too.
Some applications may install an uninstaller program that can be used to remove the application. In some cases the uninstaller may be part of the application's installer, and is invoked by clicking on a Customize button that will appear during the install process.
Some applications may install components in the /Home/Library/Applications Support/ folder. You can also check there to see if the application has created a folder. You can also delete the folder that's in the Applications Support folder. Again, they don't do anything but take up disk space once the application is trashed.
Some applications may install a startupitem or a Log In item. Startupitems are usually installed in the /Library/StartupItems/ folder and less often in the /Home/Library/StartupItems/ folder. Log In Items are set in the Accounts preferences. Open System Preferences, click on the Accounts icon, then click on the LogIn Items tab. Locate the item in the list for the application you want to remove and click on the "-" button to delete it from the list.
Some software use startup daemons or agents that are a new feature of the OS. Look for them in /Library/LaunchAgents/ and /Library/LaunchDaemons/ or in /Home/Library/LaunchAgents/.
If an application installs any other files the best way to track them down is to do a Finder search using the application name or the developer name as the search term. Unfortunately Spotlight will not look in certain folders by default. You can modify Spotlight's behavior or use a third-party search utility, Easy Find, instead. Download Easy Find at VersionTracker or MacUpdate.
Some applications install a receipt in the /Library/Receipts/ folder. Usually with the same name as the program or the developer. The item generally has a ".pkg" extension. Be sure you also delete this item as some programs use it to determine if it's already installed.
There are many utilities that can uninstall applications. Here is a selection:
AppZapper
Automaton
Hazel
CleanApp
Yank
SuperPop
Uninstaller
Spring Cleaning
Look for them at VersionTracker or MacUpdate.
For more information visit The XLab FAQs and read the FAQ on removing software.

One Way to Fix the "System Extension Cannot Be Used, AppleUSBEthernetHost.kext" Error...

I found (one) way to fix this error...well, at least it worked for me (see below):
There seem to be various threads addressing this issue and no "one" way is the right way for everyone. I'm running my Macbook on OS X 10.6.8 (Snow Leopard). Once I installed the iTunes update, two things happened: my iPhone became corrupted when I sync'd via USB and then my iTunes stopped recognizing the iPhone as a "sync-able" device -- meaning it would show up on iTunes but when you went to click sync, the sync button was unavailable.
I tried locating the .kext file, deleting it, repairing it, replacing with an older version, entered different commands in terminal but I kept getting the same error. Ultimately, I fixed the problem fairly simply, but it may not be something everyone is willing to do. If you have an external hard-drive and had your computer hooked up to Time Machine, this is what you should do:
Hopefully you'd been backing your computer up automatically fairly recently, and you have some this stored on an external hard drive via Time Machine from before iTunes 11.4 was downloaded onto your computer.
If you haven't done so already, and your iTunes library isn't corrupt, Backup your entire iTunes library to an external hard-drive (if you don't care about your library, ignore this step...this procedure might not work, however, if your first backup of your iTunes library is via version 11.4. If you go through all of these steps and you encounter the same problem, restore your itunes to an older version via Time Machine, then redo steps)
To do this, create a new Folder on your hard drive and call it "iTunes"
Go into your iTunes preferences > Advanced > under "iTunes Media folder location" we want it to say /Volumes/(Your Hard Drive Name)/iTunesNext to the "iTunes Media folder location" dialogue box, it should read CHANGE or RESET. Click CHANGE, navigate to your external hard drive and locate the newly created iTunes folder...your computer should automatically start to transfer your library to the new destination.
Backup and "new files" on your computer that you create since updating your iTunes to version 11.4 (i.e. new iCal entries, documents)
Backup your important files (I have mine in dropbox but chose to be safe and backed them up on an external hard drive as well)
Once you have everything saved, you're going to want to go through the process of completely restoring your entire computer (essentially wiping it clean).
To do this on Snow Leopard, you need to have the Mac OS X Snow Leopard Installing disc.
Insert disc > when the Install screen pops up, select Utilities... > it will then prompt you to Restart your computer
After your computer restarts, it will prompt you to reinstall Snow Leopard or select a different option from Utilities which can now be found at the top of your screen on the toolbar. From there, select the option that is along the lines of Restore from Backup Using Time Machine and then select which backup you want to restore your computer to ... since iTunes 11.4 went live on Sept. 10th, I would restore to any date before that.
When your computer restores itself to your chosen backup, your computer should be exactly as it was on that date, iTunes included. It's as if nothing ever happened.
To do this on any later OS X, I believe you have to restart your computer and then hold COMMAND+R before the grey screen appears. From here, I believe it will prompt you similarly to the Snow Leopard procedures 1-3 as listed just above this bullet point.
When your computer prompts you to update iTunes to version 11.4 from whatever version you reverted back to, DO NOT UPDATE. Keep your old iTunes version and wait for this thing to be addressed by Apple.
This procedure worked for me and although it's a bit tedious, it fixed both my iTunes and iPhone errors. Note: I did have to erase and restore my iPhone through an old backup via iTunes once iTunes was working again. Try it out. See if it works for you. MAKE SURE YOU BACKUP YOUR FILES BEFORE ATTEMPTING ANY FULL SYSTEM RESTORE.

There's more to it than this IMHO. Here is my explanation:
If I go back in my Time Machine backups and restore the previous version before I installed iTunes 11.4, the version of that same kext was also listed as being "7.0" despite being older and twice the size (120400 bytes vs. 63024 bytes in the 11.4-installed version).
(The older version is "BuildVersion 305" and "SourceVersion 122000000000000"; the new 11.4 version is "BuildVersion 417" and "SourceVersion 113000000000000".)
The real problem is this:
/System/Library/Extensions/AppleUSBEthernetHost.kext/Contents/_CodeSignature used to contain
-rw-r--r--+ 1 root wheel 172 Jan 31 2014 CodeDirectory
-rw-r--r--+ 1 root wheel    92 Jan 31 2014 CodeRequirements
-rw-r--r--+ 1 root wheel 1745 Jan 31 2014 CodeResources
-rw-r--r--+ 1 root wheel 4064 Jan 31 2014 CodeSignature
/System/Library/Extensions/AppleUSBEthernetHost.kext/Contents used to contain symbolic links down into there:
lrwxr-xr-x+ 1 root wheel    28 Jun 12 2012 CodeDirectory@ -> _CodeSignature/CodeDirectory
lrwxr-xr-x+ 1 root wheel    31 Jun 12 2012 CodeRequirements@ -> _CodeSignature/CodeRequirements
lrwxr-xr-x+ 1 root wheel    28 Jun 12 2012 CodeSignature@ -> _CodeSignature/CodeSignature
When iTunes 11.4 was installed via Software Update/App Store, it removed CodeDirectory/CodeRequirements/CodeSignature but it did not remove the corresponding symbolic links. Presumably that is what triggered the "cannot be used" pop-up message.
Trashing the kext and installing it from the downloaded 11.4 .dmg does not create the symbolic links, thus avoiding the problem.
Obviously rolling back to the previous (Jan 2014) kext will fix the problem as well as the symbolic links point to files that exist.
(I'm really curious to know what happened between BuildVersion 305 and BuildVersion 417 that caused it to shrink nearly by half. It looks to me like the Code Signing stuff got ripped out - Lord knows why.)

HP Laser Printer message saying "System Extension Cannot Be Used"

I am trying to install a laserjet printer but while it was installing, a message came up which read, "'System Extension Cannot Be Used' The system extension, "/System/Library/Extensions/AppleUSBEthernetHost.kext' was installed improperly and cannot be used. Please try reinstalling it, or contact the product's vendor for an update." We tried the printer out and it seems to work, however, the scanner does not work.
When I got this Mac Book Pro, 4 or 5 years ago, I had a HP inkjet printer which I can never use the scanning feature because it did not work. I don't remember what the error message was, but it never worked when I tried to use it. I wonder if the problems with scanning have to do with this particular file that is supposedly installed wrongly.
We tested the printer out and it worked fine. But no scanning. It can't find the scanner.
My computer is Mac OS X - 10.6.8. The printer is HP Laserjet Pro 200 color MFP.
Anyone have any idea what I should do to fix this error? Thanks.

Open the Script Editor in the /Applications/AppleScript/ folder, copy and paste the entire following line into it, and press the Run button:
do shell script "chown -R root:wheel /System/Library/Extensions/AppleUSBEthernetHost.kext" with administrator privileges
If it doesn’t work, choose Go to Folder from the Finder's Go menu, provide /System/Library/Extensions/ as the path, throw the AppleUSBEthernetHost.kext item away, and reinstall iTunes.
(118910)

Framemaker uses $filename for short file name, can we edit this to change appearance? We do not want the short file name of long filename to include the .fm extension can this be removed or modified to make this happen?

Framemaker uses <$filename> for short file name, can we edit this to change appearance? We do not want the short file name of long filename to include the .fm extension can this be removed or modified to make this happen? In compiling our books it would be helpful to not have this extension appear as it then requires us to create extra files without them.

See: System Variables

I want to reinstall my operating system,How can I back up all my add ons, extensions and personas for reinstallation when Im done?

I want to reinstall my operating system,How can I back up all my add ons, extensions and personas for reinstallation when Im done?
Im using fire ftp,downthem all,wot , antiporn pro,and various personas.
I dont want to renstall them all one at a time, rather I would like to ireinstall a back up like I do with my bookmarks,
Is this possible??

See this support article. <br />
https://support.mozilla.com/en-US/kb/Backing+up+your+information

System extension cannot be used - on startup?

Recently, I had to repair permissions after a error cause me not to be able to login. I did a startup from the disc and got in, but now these error messages come up;
System extension cannot be used
"/System/Library/Extensions/SymIPS.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;
"/System/Library/Extensions/SymIInternetSecurity.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;
"/System/Library/Extensions/IO80211Family.kext/Contents/PlugIns/AppleAirPortCrcm 4311.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;
"/System/Library/Extensions/IO80211Family.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update...
not to mention now it says I don't have airport card and the internet is running slower!
I have completed further repair disk permissions.
What can I do?
Thanks.

HI,
*"System extension cannot be used"*
*"/System/Library/Extensions/SymIPS.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;*
*"/System/Library/Extensions/SymIInternetSecurity.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;*
*"/System/Library/Extensions/IO80211Family.kext/Contents/PlugIns/AppleAirPortCrc m4311.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... and;*
*"/System/Library/Extensions/IO80211Family.kext" was installed improperly and cannont be used. Please reinstalling it, or contact the vendor for an update... "*
Is this the results of booting from your install disk and using Disk Utility to Verify the drive, or just repair permissions?
Carolyn

System extension cannot be used error message

I keep getting a message:
The system extension “/System/Library/Extensions/IOFireWireWDHID.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update.
I no longer use a Western Digital external hard drive so I am not sure how to remove this file so that I no longer get this message. Can anyone take me through the steps to fix this issue?
Thanks,
Allison
OSX 10.8.2
iMac 2011
3.1 GHz Intel Core i5

Hello,
See if the WD Installer has an uninstall function... you really don't need it at all.

System extensions can't be used

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