How to fix “iTunes was unable to load dataclass” error
I started getting the annoying “iTunes was unable to load dataclass information from Sync Services. Reconnect or try again later.” error when i installed iPhone 3.0 beta onto my 1G iPhone. I have uninstalled iTunes (version 8.1), uninstalled Apple’s Mobile Device Support and reinstalled both of them but that did not fix the problem. I have also installed an older version of iTunes but that did not help as well. The error is not just annoying, i was not able to restore from my iPhone backups. I made a mistake in getting iPhone 3.0 beta onto my iPhone and instead of “update”, i chose “restore”. That wiped out all the App Store applications that i had installed. I could easily re-install the applications but there was no way for me to restore the saved data for some of the apps like eWallet and Gas Cubby. Until iPhone 3.0 beta is jailbroken, restoring a backup is the only way that i am aware of that can restore the app data.
From the Console log, i noticed these errors were generated whenever an iPhone is connected to my Mac Pro:
3/19/09 10:57:50 PM [0x0-0x17a17a].com.apple.iTunes[4049] MobileDevice: _read_callback: Could not receive message
3/19/09 10:58:02 PM [0x0-0x11011].com.apple.systemuiserver[233] DigiHub:sendChargingCommandToDevice RequestExtraPower(kUSBPowerDuringWake) returned 0
3/19/09 10:58:02 PM [0x0-0x11011].com.apple.systemuiserver[233] DigiHub:sendChargingCommandToDevice sending command with sleep: 0, wake 0
3/19/09 10:58:02 PM [0x0-0x11011].com.apple.systemuiserver[233] DigiHub:sendChargingCommandToDevice sending command with sleep: 0, wake 0
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Parent: Can't write length for data
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Parent: write to child failed, trying to create child again...
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Exec of child with pid 4100 failed with error 255
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Exec for child /System/Library/PrivateFrameworks/MobileDevice.framework/Versions/Current/AppleMobileDeviceHelper.app/Contents/MacOS/AppleMobileDeviceHelper failed or inexplicably returned
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Parent: Can't write length for data
3/19/09 10:58:05 PM [0x0-0x17a17a].com.apple.iTunes[4049] Parent: Can't talk to child
So i decided to get rid of everything in /System/Library/PrivateFrameworks/MobileDevice.framework and re-installed Apple Mobile Device Support. Voila, that worked!
Hi, Im having the same problem, this annoying message is displayed every single time I connect my Iphone, I already uninstall Itunes, and also did what you say worked for you. I installed Itunes again and again and the message still there.
Any suggestions for me?
Please help I don’t know what else to do
Thanks
@Gilbert:
Have you tried the following?
http://ktula.com/2009/04/19/how-to-fix-itunes-could-not-back-up-the-iphone-error/
Thanx so much! I tried everything for weeks but this finally works. Thanks again!