iPod Touch 2nd generation not supported under iTunes 12.8 or later

UPDATE 2018-12-08: The iPod Touch 2nd generation running iOS 4 is now supported in macOS Mojave 10.14.2 using iTunes 12.9.2.5

Thanks to Devin for pointing out the return of support in Mojave in the comments.

I don't know if Apple will bring support to iTunes 12.8 or earlier versions of iTunes 12.9.
MacOS High Sierra 10.13.6 with Security Update 2018-003 has iTunes 12.8.0.150 and does not support the iPod Touch 2nd generation.

END UPDATE

 

The iPod Touch 2nd generation (model A1288) running iOS 4 is not supported under iTunes 12.8 or later.

I have verified this with extensive testing on multiple platforms, with multiple versions of the operating system and iTunes.

The error you will see on iTunes 12.8 and later is: iTunes could not connect to the iPod touch "[iPod Touch name]" because an invalid response was received from the device.

The last version of iTunes that I can confirm supported the iPod Touch 2nd generation is 12.7 (specifically 12.7.4.80)

(Hereafter I will use iPod Touch 2gen to refer to the iPod Touch 2nd generation.)

This means that the last version of macOS that will support the iPod Touch 2gen is macOS High Sierra (OS X 10.13) specifically OS X 10.13.6 and only if you don't install the App Store upgrade to iTunes 12.8

macOS Mojave (OS X 10.14) has iTunes 12.9 which is not compatible with the iPod Touch 2gen.

It's my understanding that Apple has discontinued iOS 4 device support starting with iTunes 12.8

Details

The iPod Touch 2nd generation, model A1288 released 2008-09 and running iOS 4 (latest version iOS 4.2.1) will connect immediately and be displayed as a device without any issues in iTunes 12.7

When connected to the same computer running iTunes 12.8, after a delay of over a minute the computer will finally display the error message: iTunes could not connect to the iPod touch "[iPod Touch name]" because an invalid response was received from the device.

The same error message will be displayed when an iPod Touch 2gen is connected to a computer running iTunes 12.9

There is no way to fix this error.

If this is Apple's intended behaviour, it would be much better if iTunes immediately displayed an error e.g. "iOS 4 devices are no longer supported", rather than taking over a minute to give an error that makes it look like it is a device problem, not an iTunes problem.

In order to find your iPod model, see Apple Support - Identify your iPod model.

I spent hours going step-by-step through Apple's troubleshooting steps for iPod device connection problems on multiple computers and operating systems (Apple Support documents Resolve issues between iTunes and third-party security software and If iTunes doesn't recognize your iPhone, iPad, or iPod) and it was literally a waste of time; it's not a device problem, it's an iTunes problem, the iPod Touch 2nd generation works fine, it's just that iTunes 12.8 and later no longer support it.

The only options for continuing to use the iPod Touch 2nd generation require a substantial degree of technical skill, and all of them have risks.  If you do want to investigate the options below, do so at your own risk. Make sure you have a complete backup and you know how to recover your computer from backup before you start, as you may totally screw up your computer.
I disclaim any responsibility for your results.

Understand that iTunes is very deeply embedded into and integrated with your operating system, and that different iTunes versions have different support files, with older versions of iTunes often unable to read newer library files. 

It is NOT as simple as just deleting iTunes.app and running an installer for a previous version of iTunes.  In fact both High Sierra (OS X 10.13) and Mojave (OS X 10.14) have operating system protection to prevent you from deleting iTunes.app, even as an administrative user.

SIDEBAR: I have also documented this issue (in much less detail) in Apple Discussions - iPod Touch 2nd gen will [no] longer sync with newer iTunes.  END SIDEBAR

Scenarios

If you have an iPod Touch 2gen (or other iOS 4 device) you are probably facing one of the following three scenario:

• You currently have High Sierra OS X 10.13 (or earlier) with iTunes 12.7 (or earlier) - in this case, congratulations, your iPod Touch 2gen should work.  Make a complete backup of your current setup.  Consider maintaining that backup as a separate bootable installation just to support the iPod Touch 2gen.
• You have High Sierra but you installed the iTunes 12.8 update - the iPod Touch 2gen won't work in this configuration and it is difficult to fix
• You updated to Mojave OS X 10.14 (or bought a computer with Mojave already on it) - the iPod Touch 2gen won't work in this configuration and it is very difficult to fix

Options

When considering options, it's basically a case of whether you have a currently working setup, a backup of a working setup, or are willing to do a brand new separate macOS installation.
I really strongly recommend that you do a completely separate macOS installation, leaving your current primary macOS setup unchanged.  This is by far the safest and easiest option.

However, none of these options are good, and some require extra hard drives and the understanding of how to switch between different macOS setups.

1. Completely Separate Secondary Install to Support Your Device

The best option is to make a completely separate macOS High Sierra (OS X 10.13) install, e.g. in a virtual machine or on a second internal drive or an external drive.  Then maintain that installation with iTunes 12.7 -- don't let the App Store update to iTunes 12.8.  (Of course this also applies to previous versions of the OS such as Sierra OS X 10.12 and earlier, with earlier versions of iTunes, if that's the configuration you have.) 

This install could be a clone of your current install e.g. from a Time Machine backup or by using e.g. SuperDuper to copy your current install.  Or it could be a completely clean install using the High Sierra installer, e.g. downloaded from the App Store on a Mac running High Sierra or earlier.

Note that the High Sierra installer is not available in the App Store on computers running macOS Mojave (OS X 10.14) and also note that even if your original OS was High Sierra (OS X 10.13), the Recovery Mode (macOS Recovery) installer will be replaced with a Mojave (OS X 10.14) installer when you install Mojave.  Once Mojave is installed one of the only ways to access the High Sierra installer on a computer that originally came with High Sierra is to use Internet Recovery (macOS Recovery over the Internet).

UPDATE: Also note that Apple has removed High Sierra from App Store search.  It is not possible to search for the High Sierra installer and as far as I know it's not possible to browse to it either.  You will need to use a direct App Store link, either this Apple shortlink https://apple.co/2QkIDsb or this long link https://itunes.apple.com/ca/app/macos-high-sierra/id1246284741?mt=12 or go to Apple Support article How to upgrade to macOS High Sierra https://support.apple.com/en-ca/HT208969 END UPDATE

In this option of using a separate install, you would basically switch to the separate installation for all activities associated with the iPod Touch 2gen or other iOS 4 device.  This will be a hassle particularly in terms of your iTunes Library, which you may need to start again from zero by re-importing files, or try the much more complicated step of copying the library to the new separate installation.  I have not documented the process of copying your iTunes Library.

For this procedure, you will need to inform yourself. Please don't proceed unless you fully understand all the steps and risks involved.

• Apple Support - About macOS Recovery
• Apple Support - How to reinstall macOS from macOS Recovery
• MacWorld UK - 24 Sep 18 - How to make a bootable macOS installer on an external drive
• MacWorld UK - 24 Sep 18 - How to run macOS from an external drive
• MacWorld UK - 01 Oct 18 - How to downgrade macOS from Mojave to an older version - downgrading your OS is not recommended

UPDATE 2018-11-25: When creating an external bootable install, be aware that newer Mac computers such as the Mac mini 2018 have extra layers of security, specifically Startup Security Utility.

You will need to go into Recovery Mode and then Utilities -> Startup Security Utility and change the default External Boot - Disallow booting from external media to Allow booting from external media.

Also, you may find that external boot drives are not portable across Macs.  For example a High Sierra external boot drive created for a Mac mini 2014 may not work on a Mac mini 2018.

END UPDATE

UPDATE 2018-12-01: WIth the Mac mini 2014 discontinued, another option is to get a completely separate computer, rather than making an external bootable install.  The Mac mini 2014 may be available new for a brief window as vendors close out their inventory, and also available a refurbished computer.

END UPDATE

2. Restore a Previously Working Backup for your Primary Installation - NOT RECOMMENDED

If you use Time Machine and previously had a working macOS configuration that supported the iPod Touch 2gen, you could use Time Machine to revert your primary install to the backup of that working configuration.  However note that it may be difficult if not impossible to isolate just iTunes from the backup; you probably have to do a full restore, which means you may lose any subsequent files created. 

Note that it's the combination of iTunes, AND all its support files, AND the library, .itl and other files associated with that specific iTunes version.  An older version of iTunes WILL NOT WORK with newer versions of the support files and library. 

Also, there are security risks in running an older version of the operating system rather than updating to the latest version that your computer supports.  Trying to maintain your primary install on an older version of macOS and iTunes is attempting to freeze your computer in time, and it just isn't a good idea.  This option is not recommended.

3. Downgrade the Version of iTunes - STRONGLY NOT RECOMMENDED

You can try to downgrade the version of iTunes within High Sierra or Mojave.  Although I have documented this procedure, it is really really not recommended.  It requires over-riding operating system protections and really extensive file deletions across the file system.  It's highly destructive and risky, and it is not the way macOS is intended to operate.  An older version of iTunes running in e.g. Mojave may cause problems with the rest of the operating system, and may break iTunes and/or macOS in subsequent App Store updates.  THIS OPTION IS STRONGLY NOT RECOMMENDED.

Comments

[Oscar Arce]

Thank you. After reading and trying several troubleshooting guides, restoring the iPod to its original factory settings, etc... yours is the only source that I found that makes sense and explains the ambiguous "invalid response" message. As you clearly outline, the only option is really to have a secondary install... which is for me, too much of a waste of resources just to keep using this nice old iPod. In my case, after managing to start to restore the iPod to its original settings, now it ask me to connect to itunes to finish up the restoration... So, I ended wit an iPod that is unusable by itself. As you said, a simple warning telling users that "iOS 4 is no longer supported", would have saved me a lot of time.

[Devin]

Looks as if this has been fixed with a Mojave update. Thank you!!

[Brian Haas]

Hugely useful post. I also wasted way to much time on this after finding my trusty iphone3G (which I use as an ipod) is no longer supported. Apple could have made the error message far more clear and saved us all a lot of effort. It's sad that my still otherwise healthy and working 3G can no longer be used.

[Oscar Arce]

Devin said "Looks as if this has been fixed with a Mojave update.". Yes, that is true. With Mojave 10.14.2 I am able now to sync music to my old iPod touch now. Thanks.