FIX: iTunes 12.9.5.5 on macOS Mojave with iOS 27
After upgrading my iPhone SE (3rd generation) to iOS 27.1, iTunes 12.9.5.5 on macOS Mojave 10.14.6 could detect the iPhone but could no longer communicate with it.
iTunes requested additional software, but the automatic update installed MobileDevice 1827.100.17.100.1, which did not resolve the problem.
I found that installing Apple's MobileDevice 1860.2.5.100.2 package restored communication.
The solution:
- Back up your Mac before proceeding.
- Obtain Apple's MobileDeviceOnDemandPackage.pkg, containing version 1860.2.5.100.2.
- The original Apple download URL is:
https://swcdn.apple.com/content/downloads/34/26/142-23719-A_6Y4LUO96P3/ytfk8y0jpnp9ud3lpim9ebbts4n7qsrww8/MobileDeviceOnDemandPackage.pkg
Note: This URL has returned HTTP 403 errors, so another trusted source may be needed.
- Save the package in your Downloads folder.
- Verify its Apple signature in Terminal:
- pkgutil --check-signature ~/Downloads/MobileDeviceOnDemandPackage.pkg
- Quit iTunes, disconnect your iPhone, and install the package:
- sudo installer -pkg ~/Downloads/MobileDeviceOnDemandPackage.pkg -target /
- Restart your Mac.
- Verify the installed MobileDevice version:
- defaults read /System/Library/PrivateFrameworks/MobileDevice.framework/Resources/version.plist
- Confirm that CFBundleVersion shows 1860.2.5.100.2.
- Open iTunes and reconnect your iPhone.
Result: iTunes successfully recognized my iPhone and displayed its Summary page, iOS version, storage capacity, and device information.
I first tested this on a clean Mojave installation on a separate drive, then successfully repeated it on my main Mac Pro 5,1.
No SIP modifications or manual replacement of system files were necessary.
A local iPhone backup was done.
Disclaimer: This is an experimental workaround tested on my configuration, not an Apple-supported solution. Always back up your Mac before attempting it.
