system extension cannot be used AppleUSBEthernetHost.kext

"What version/build number shows up in your About iTunes window? Mine is 10.4 (18)"

Same here, but I'm using the "iTunes 11.4++" version from Sept. 23rd.

There's no guarantees that the older, original iTunes 11.4 release (from September 9th or thereabouts) doesn't also say "10.4 (18)" as well.

If dataminer007 hasn't changed his original Sept. 10th iTunes 11.4 install, maybe he could check the version/build number to confirm/deny?

I just reinstalled the latest version of iTunes and the HP drivers per Greg Earle's instructions, so I can't confirm the build of my previous version of iTunes.

"I just reinstalled the latest version of iTunes and the HP drivers per Greg Earle's instructions, so I can't confirm the build of my previous version of iTunes."

D'oh!@

(On a more hopeful note, did that fix your problem? Also - what vintage Mac and OS is this on?)

No error message so far.

I have a 20 inch mid 2007 iMac Processor 2.4 GHz Intel Core 2 Duo, Software OS X 10.9.5 (13F34).

I plan to buy my next iMac the next time they are upgraded.

Greg,

You were correct when you said "vintage". 7 years is a long time time to have a computer. This is my 4th iMac and it seems that I am able to keep them longer and longer. But it is time to upgrade.

BTW, thanks to everyone and especially Greg. This is a wonderful resource to have.

"I have a 20 inch mid 2007 iMac Processor 2.4 GHz Intel Core 2 Duo, Software Mac OS X 10.9.5 (13F34)."

OK - good to know. Just checking to make sure you didn't have a 32-bit-only, 2006-vintage Core Duo-or-older system.

So we know that 64-bit capable (like your Core 2 Duo iMac), Mavericks-running machines can also get these same "The system extension “/System/Library/Extensions/AppleUSBEthernetHost.kext” was installed improperly and cannot be used." error messages as well.

The important thing is that for these systems, knowing that trashing the now-damaged AppleUSBEthernetHost.kext and re-installing iTunes 11.4++ and whatever other software (be it HP drivers or otherwise) that provoked the error will now fix the issue.

(USB tethering is probably still broken even on those "newer" 64-bit systems, but at least those could potentially be fixed - 10.6.8/32-bit owners are stuck.)

I looked through /Library/Receipts/InstallHistory.plist for installation dates and found out that my iTunes was updated by Software Update to 11.4 (18) on 2014-09-16. Thus the build numbers are the same for the original and for the later iTunes 11.4 versions, the one Greg calls "iTunes11.4++". There was no error message regarding AppleUSBEthernetHost.kext at that time.

Two weeks later I installed the HP Printer Software Update version 3.0 on 2014-10-02 and immediately received the kext error. The HP update caused a rescan of the extensions and that's when the system recognized that the AppleUSBEthernetHost.kext, apparently introduced by iTunes 11.4, was faulty. Looking through previous system logs I find these entries at the time of the HP update:

Oct 1 20:52:28 Aptas-MacBook-Pro.local com.apple.kextd[12]: Rescanning kernel extensions.

Oct 1 20:52:28 Aptas-MacBook-Pro.local com.apple.kextd[12]: Cache file /System/Library/Caches/com.apple.kext.caches/Directories/System/Library/Extensi ons/KextIdentifiers.plist.gz is out of date; not using.

Oct 1 20:52:28 Aptas-MacBook-Pro.local com.apple.kextd[12]: Cache file /System/Library/Caches/com.apple.kext.caches/Startup/IOKitPersonalities_x86_64. ioplist.gz is out of date; not using.

Oct 1 20:52:30 Aptas-MacBook-Pro.local com.apple.kextd[12]: Can't load AppleUSBEthernetHost.kext - authentication problems.

Oct 1 20:52:30 Aptas-MacBook-Pro kernel[0]: Resetting IOCatalogue.

and right after the HP installation:

Oct 1 20:52:44 Aptas-MacBook-Pro.local com.apple.kextd[12]: Rescanning kernel extensions.

Oct 1 20:52:44 Aptas-MacBook-Pro.local com.apple.kextd[12]: Cache file /System/Library/Caches/com.apple.kext.caches/Directories/System/Library/Extensi ons/KextIdentifiers.plist.gz is out of date; not using.

Oct 1 20:52:44 Aptas-MacBook-Pro.local com.apple.kextd[12]: Cache file /System/Library/Caches/com.apple.kext.caches/Startup/IOKitPersonalities_x86_64. ioplist.gz is out of date; not using.

Oct 1 20:52:44 Aptas-MacBook-Pro.local coreaudiod[287]: Enabled automatic stack shots because audio IO is inactive

Oct 1 20:52:46 Aptas-MacBook-Pro.local com.apple.kextcache[6764]: rebuilding /System/Library/Caches/com.apple.kext.caches/Startup/kernelcache

Oct 1 20:52:46 Aptas-MacBook-Pro kernel[0]: Resetting IOCatalogue.

Oct 1 20:52:47 Aptas-MacBook-Pro.local com.apple.kextcache[6766]: AppleUSBEthernetHost.kext is not authentic; omitting.

Oct 1 20:52:51 Aptas-MacBook-Pro.local com.apple.kextcache[6768]: / locked; waiting for lock.

"I looked through /Library/Receipts/InstallHistory.plist for installation dates and found out that my iTunes was updated by Software Update to 11.4 (18) on 2014-09-16. Thus the build numbers are the same for the original and for the later iTunes 11.4 versions, the one Greg calls "iTunes11.4++". There was no error message regarding AppleUSBEthernetHost.kext at that time."

That's why this stuff is so insidious. Apple quietly updated the installer, didn't tell anyone, and didn't change the "visible" version number (i.e. the "11.4 (18)") for anyone to notice it was subtly different. You literally had to go down into some .plist files to see the slight change in some versioning variables to tell.

BTW I am a pack-rat so I still have a few old versions lying around. The newer iTunes 11.4 .dmg actually got smaller than the original by almost 1/2 a MB.

[17:02] nightowl:/<2>Disk images/iTunes % ls -ltFr

total 1631408

-rw-r--r--@ 1 earle  staff   14507195 Oct 12  2006 iTunes5.0.1.dmg

-rw-r--r--@ 1 earle  staff   58621179 Sep  9  2008 iTunes8.dmg

-rw-r--r--@ 1 earle  staff   98180859 May  2  2010 iTunes9.1.1.dmg

-rw-r--r--@ 1 earle  staff  178545308 Jun 13  2012 iTunes10.6.3.dmg

-rw-r--r--@ 1 earle  staff  242940774 Sep  9 05:52 iTunes11.4.dmg

-rw-r-----@ 1 earle  staff  242433227 Sep 25 13:17 iTunes11.4++.dmg

(Look at the progression of the file sizes. Bloatware, anyone?)

Greg Earle wrote:

"I installed iTunes 11.4 on Sept 10th and until I installed the new HP Printer Driver, this error message has never occurred."

That was the original iTunes 11.4 release, which biffed everything.

Apple quietly replaced that version with an updated version back on Sept. 23rd or 24th, without telling anyone.

My advice to you (and to zspy7274, and anyone else similarly afflicted) would be:

1. Trash /System/Library/Extensions/AppleUSBEthernetHost.kext
2. Reboot
3. Re-download iTunes 11.4 (I call it "11.4++") from the Apple iTunes download page
4. Re-install iTunes from the downloaded .dmg file (the .dmg file size should be 242433227 bytes - if it's 242940774 bytes, you have the old/bad version!)
5. Re-install your HP printer drivers
6. Reboot
7. ...
8. Profit!!!

Can you confirm that this fixes the missing iPhone-as-a-network-connection problem? When I have my iPhone plugged in via the USB, it does not show up as a network interface for tethering. I can only use the iPhone for tethering over Bluetooth or Wifi.

"Can you confirm that this fixes the missing iPhone-as-a-network-connection problem? When I have my iPhone plugged in via USB, it does not show up as a network interface for tethering. I can only use the iPhone for tethering over Bluetooth or Wi-Fi."

No, it does not fix USB tethering.

The AppleUSBEthernetHost.kext that comes with iTunes 11.4 (or "11.4++") is busted, just like every version of the .kext since back to at least 2.3.0 or maybe even 2.2.0. 😟

Greg Earle wrote:

"Can you confirm that this fixes the missing iPhone-as-a-network-connection problem? When I have my iPhone plugged in via USB, it does not show up as a network interface for tethering. I can only use the iPhone for tethering over Bluetooth or Wi-Fi."

No, it does not fix USB tethering.

The AppleUSBEthernetHost.kext that comes with iTunes 11.4 (or "11.4++") is busted, just like every version of the .kext since back to at least 2.3.0 or maybe even 2.2.0. 😟

Yep. Definitely busted. I just tried a reinstall. Killed the kext* first and emptied trash, installed iTunes and then tried to reload the kernel extension. Joy. This is the result on an Early 2008 MacBook4,1 running OS X Lion 10.7.5:

* For those who initially saw 'next', autocorrect has its downside. 🙂

Gaia:~ trane$ sudo kextutil /System/Library/Extensions/AppleUSBEthernetHost.kext
Password: Warnings: Executable does not contain code for architecture: i386
Can't load /System/Library/Extensions/AppleUSBEthernetHost.kext - no code for running kernel's architecture

"Gaia:~ trane$ sudo kextutil /System/Library/Extensions/AppleUSBEthernetHost.kext

Password:

Warnings: Executable does not contain code for architecture:     i386

Can't load /System/Library/Extensions/AppleUSBEthernetHost.kext - no code for running kernel's architecture."

Yep - it means you are either on a 32-bit only Mac or you are (inexplicably) running a 64-bit machine with a 32-bit kernel.

I should mention that I am on a Mac Pro with a 64-bit kernel and even with that, I couldn't load the 2.3.6 version of the .kext - I had to go back to 2.3.0 to get something that would load. But after I load it (manually via kextutil), at some point later it mysteriously gets unloaded!

So I can't fix USB tethering, even on a 64-bit system.

Greg Earle wrote:

"Gaia:~ trane$ sudo kextutil /System/Library/Extensions/AppleUSBEthernetHost.kext

Password:

Warnings: Executable does not contain code for architecture:     i386

Can't load /System/Library/Extensions/AppleUSBEthernetHost.kext - no code for running kernel's architecture."

Yep - it means you are either on a 32-bit only Mac or you are (inexplicably) running a 64-bit machine with a 32-bit kernel.

I should mention that I am on a Mac Pro with a 64-bit kernel and even with that, I couldn't load the 2.3.6 version of the .kext - I had to go back to 2.3.0 to get something that would load. But after I load it (manually via kextutil), at some point later it mysteriously gets unloaded!

So I can't fix USB tethering, even on a 64-bit system.

It's not at all inexplicable. The first few iterations of Core 2 Duo machines ran 32-bit kernels. More information here:

Mac OS X v10.6: Macs that use the 64-bit kernel

This box uses a 32-bit kernel that supports 64-bit applications. It has a 32-bit EFI, so its days are numbered with Lion. There are no updates forthcoming with this system. Shame, that, as 6 GB RAM and a 960 GB SSD ensure that it's still quite spritely despite its declining years.

I'd complain about the tethering, but I've never actually even tried to do USB tethering. So I'll hold my whining for another day. 🙂

"It's not at all inexplicable. The first few iterations of Core 2 Duo machines ran 32-bit kernels. More information here:

Mac OS X v10.6: Macs that use the 64-bit kernel

This box uses a 32-bit kernel that supports 64-bit applications. It has a 32-bit EFI, so its days are numbered with Lion. There are no updates forthcoming with this system. Shame, that, as 6 GB RAM and a 960 GB SSD ensure that it's still quite spritely despite its declining years.

I'd complain about the tethering, but I've never actually even tried to do USB tethering. So I'll hold my whining for another day."

I knew I should have qualified that "inexplicable" 🙂

Yes, I'm aware that the first Core 2 Duos (and other machines) ran 32-bit kernels.

What is "inexplicable" to me is why anyone with a 64-bit capable machine would still run a 32-bit kernel these days, given the existence of easy apps like "32- or 64-bit Kernel Startup Mode Selector", plus the fact that it lets you address all your 6 GB of RAM address space instead of 4 GB per-process.

I'm aware that someone with a 2 or 4 GB system might say "Why bother?", but to me the compelling argument is that the slight performance hit is worth it given the fact that Apple is throwing 32-bit users under the bus - either by design or by accident.

(Conveniently "forgetting" to put a dual-architecture .kext into the iTunes 11.4 distribution is another signpost on that road. The fact that they wouldn't release an updated bash and sh for 10.6.8 to cure the recent "Shellshock" UNIX® shell vulnerability is another case of throwing the users under the bus, too.)

Greg Earle wrote:

"It's not at all inexplicable. The first few iterations of Core 2 Duo machines ran 32-bit kernels. More information here:

Mac OS X v10.6: Macs that use the 64-bit kernel

This box uses a 32-bit kernel that supports 64-bit applications. It has a 32-bit EFI, so its days are numbered with Lion. There are no updates forthcoming with this system. Shame, that, as 6 GB RAM and a 960 GB SSD ensure that it's still quite spritely despite its declining years.

I'd complain about the tethering, but I've never actually even tried to do USB tethering. So I'll hold my whining for another day."

I knew I should have qualified that "inexplicable" 🙂

Yes, I'm aware that the first Core 2 Duos (and other machines) ran 32-bit kernels.

What is "inexplicable" to me is why anyone with a 64-bit capable machine would still run a 32-bit kernel these days, given the existence of easy apps like "32- or 64-bit Kernel Startup Mode Selector", plus the fact that it lets you address all your 6 GB of RAM address space instead of 4 GB per-process.

I'm aware that someone with a 2 or 4 GB system might say "Why bother?", but to me the compelling argument is that the slight performance hit is worth it given the fact that Apple is throwing 32-bit users under the bus - either by design or by accident.

(Conveniently "forgetting" to put a dual-architecture .kext into the iTunes 11.4 distribution is another signpost on that road. The fact that they wouldn't release an updated bash and sh for 10.6.8 to cure the recent "Shellshock" UNIX® shell vulnerability is another case of throwing the users under the bus, too.)

While Startup Mode Selector might be useful for a fair number of users, MacBooks are excluded from the party. Apple has absolutely disabled booting the kernel in 64-bit mode on MacBooks. This may have been undone in later iterations of the MacBook or MacBook Pro, but even holding 64 during boot has no effect whatsoever other than to elicit further keyboard wear here. An Early 2008 MacBook4,1 cannot boot to a 64-bit kernel with an un-hacked OS X. Unless, of course, there's something out there of which I don't yet know. (Always a possibility.)