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neil456 Author

Level 1

14 points

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

38 replies

austibd

Level 1

0 points

Feb 4, 2013 11:27 AM in response to spalmen

Where exactly do I find: /System/Library/PrivateFrameworks/

Thanks,

Brad

jagbloke

Level 1

0 points

Feb 5, 2013 2:06 AM in response to austibd

No, I couldn't find it either. I'd been struggling with this problem for months and most of the suggestions either seemed too complicated or referred to files that weren't on my machine.

In the end, just out of curiosity, I logged the other user off Windows (Vista) and tried iTunes again. Problem gone and now it works perfectly every time.

lfleet5

Level 1

0 points

Jul 9, 2013 9:34 AM in response to spalmen

Could you possibly let me know in what file/window to find system so I can go about doing this. My iTunes recently started to have this problem. Thanks!

jagbloke

Level 1

0 points

Jul 9, 2013 12:03 PM in response to lfleet5

Do you have more than one Windows user logged on to your machine? If so, log one (or however many you're not using) so you're the only user logged on and the problem should go away.

Jul 22, 2013 5:39 AM in response to Altaveron

This worked for me!

MGFW

Level 1

0 points

Sep 11, 2013 9:37 AM in response to spalmen

That didn't work for me, tried it 3 times with rebooting after each step - no change.

After installing latest Xcode beta i checked Organizer-Devices and pushed "restore using iTunes" and it worked.

I didn't do a restore yet but the device is syncing with iTunes now.

Sep 11, 2013 11:05 AM in response to jagbloke

/System is typically a hidden folder. If you open Finder, then from the File menu pick Go (or Command-G) you can type the path in. You must match upper and lower case.

I don't know what it would be on Windows, I have only ever had this issue on a Mac. Don't have iTunes on Windows any more.

Sep 11, 2013 8:07 PM in response to neil456

Hey guys, need some major help here if you can.

I really appreciate any feedback anyone can give!

My friend just performed a software update, bringing his iTunes to version 10.0.5 (current version).

The update went flawlessly, but now we are getting the error listed by OP when he tries to SYNC or RESTORE FROM BACKUP

iTunes was unable to load data class information from sync services

His mac is currently on OS X 10.6.8.

We have tried everything listed in this forum + other searches from google:

- Deleting and reinstalling iSync with pacifist & original OS X install disc

- Fully deleted itunes with appzapper and reinstalled,

- Removed "MobileDevice.Framework" and reinstalled iTunes (did this several times)

- I also tried a previous poster's suggestion, "Paul" on page 2, to try and stop "Apple Mobile Device" and that didnt work either. And I also followed the link he gave on his post to CNN instructions, which didnt work for me either.

We are just unable to sync or restore from backup. Everything else works totally fine.

We're really running out of options, so we appreciate whatever further advice you can give.

Thanks in advance!

iTunes was unable to load data class information from Sync Services