Is your Apple iDevice not being recognized properly in iTunes?
Have an iPhone/iPad that doesn’t want to backup or sync in iTunes?
Does iTunes popup error messages relating to Apple Mobile Device Services, iTunes unable to load class information from Sync Services, or other sync errors?
Doing a simple web search will provide numerous links showing these problems, and Apple has not provided an easy solution to them at the moment. After dealing with these issues a few times – I came up with a simple solution that has worked consistently.
Since iTunes 11 – you cannot easily revert to iTunes 10.7, so downgrading or uninstalling/reinstalling iTunes is not an option.
First Step
(These are taken from, and detailed here : http://support.apple.com/kb/HT1747)
• Disconnect your device from your Mac.
• Choose Go > Go to Folder.
• Enter /System/Library/Extensions and click Go.
• Locate the file AppleMobileDevice.kext and drag it to the Trash.
• Choose Go > Go to Folder.
• Enter /Library/Receipts/ and click Go.
• Locate the file AppleMobileDeviceSupport.pkg and drag it to the Trash.
• Restart the computer.
• Choose Finder > Empty Trash and restart the computer.
Second Step
• Download/install Xcode from the App Store.
• Choose Go > Go to Applications.
• Right Click on the Xcode icon and select Show Package Contents.
• Navigate to /Contents/Resources/Packages/ and install the MobileDevice.pkg
• Connect your device and enjoy a clean backup / sync.
That is it!