Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

iTunes was unable to load data class information from Sync Services

Not sure when it started, but I just noticed that my devices are not backing up when i sync in itunes.


This includes both iPad, iPhone 4s with 6.0.1 (10A523), Mac Lion 10.7.5, and iTunes 10.7 (21). Includes both WiFi and USB connections.


I get a lot of these in the logfile:


11/18/12 10:12:45.117 AM taskgated: killed com.apple.SyncServices.AppleMobileDeviceHelper[pid 1761] because its use of the com.apple.private.tcc.allow entitlement is not allowed

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Exec for child /System/Library/PrivateFrameworks/MobileDevice.framework/Versions/Current/Apple MobileDeviceHelper.app/Contents/MacOS/AppleMobileDeviceHelper failed or inexplicably returned

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Parent: Can't write length for data

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Parent: Can't talk to child

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Parent: Can't write length for data

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Parent: write to child failed, trying to create child again...

11/18/12 10:12:45.117 AM [0x0-0x63063].com.apple.iTunes: Exec of child with pid 1761 failed with error 255


Applications are updated on the device, but my backups do not occur and iTunes summary says, "Last backup to this computer: Unknown".


When I connect the device I always get, "iTunes was unable to load data class information from Sync Services. Reconnect or try again later."


I have reset sync services, rebooted Mac, rebooted iPhone, repaired permissions, and reinstalled iTunes. All of which had no effect on solving the problem.

iPhone 4S, Mac OS X (10.7.5)

Posted on Nov 18, 2012 8:33 AM

Reply
38 replies

Dec 4, 2012 7:04 PM in response to spalmen

spalmen wrote:


/System/Library/PrivateFrameworks/MobileDevice.framework


FWIW, after deleting it, I restarted, then reinstalled iTunes 11. This cleared the sync issue for all my devices. Good luck!

Works like a charm!

I too think like you, . . . after deleting, I cleared trash, rebooted, reinstalled iTunes 11 & then re-synced.


Re-solved!!🙂

Jan 4, 2013 2:08 AM in response to neil456

Hey thanks for the help, I was wondering why I was getting this error (turns out it was from installing the XCode Dev Preview).


I had to look up how to reinstall iTunes, since I assumed I had to uninstall it first, but that's definitely not the case. You can just download the installer from Apple. Thanks everyone!

Feb 3, 2013 3:05 PM in response to neil456

Had this problem for ages. Went through all the solutions, mostly didn't have the folders I was told to delete or don't have Outlook, blah blah. Didn't want to uninstall iTunes.


Guess what? I was logged on as a different user. Just logged my wife off (so I was the only user on the machine) and Bob's the proverbial (if you're American that probably won't mean much but it made me smile).


Happy days.

iTunes was unable to load data class information from Sync Services

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple ID.