MobileDeviceHelper has stopped working - and will not stop stop-working!

Hello.

First off, let me state that at one time iTunes and the syncing of my iPhone and iPod Touch worked great on my laptop (an HP dv5t running 64bit Win Vista). Two months ago when Apple updated iTunes from version 9.0.3 to 9.1 there seemed to be many people who encountered errors (syncing issues). Me included. I decided to wait and see what solutions might pop up - either in forums or in the form of an update from Apple. Soon Apple released 9.1.1. Unfortunately, the update did not fix my issues and I am still unable to use iTunes on my laptop.

Here is what is happening:

iTunes alone works fine. I can open it, play music, see my apps, etc.

As soon as my iPhone (or iPod) is connected to the laptop I get persistent messages that "MobileDeviceHelper has stopped working" as well as "iTunes was unable to load dataclass information from Sync Services." These messages cause the iTunes application to lockup and the only way to stop them from appearing is to unplug the iPhone from the computer.

I have tried 'repairing' iTunes, deleting the iTunes preferences files as suggested on Apple's main support page, reinstalling, reverting to previous version of iTunes, doing so with great care to remove any remnants of former installs. I have also attempted some of the .dll fixes as suggested by earlier posts (moving around libxml.dll, or similar files, from the windows directory and seeing if anything changes). No luck.

If there has been a fix for this then I apologize for this post, but I have not seen any 'solution' that works for me. Any help would be greatly appreciated.

Jeff Hollon

HP dv5t Laptop, Windows Vista, 64bit

Posted on Jun 5, 2010 8:13 AM

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10 replies

Jun 7, 2010 8:11 PM in response to JeffHollon

I should also mention that I can get previous versions of iTunes (specifically 9.0) to sync with my iPhone and iPod, however updating a working 9.0 to 9.1.1 still fails to sync (same errors). Getting the previous version working is a pain: I have to uninstall ALL Apple related software from my laptop, reboot and run CCleaner, then install the iTunes 9.0 software.

I am hoping for a fix to this because I am getting an iPad soon and wish to be able to use it with my laptop ASAP.

Jul 15, 2010 8:42 PM in response to JeffHollon

Hello. I was able to get my iTunes to start working normally again. I had to do a few things. Not sure if this is exactly what fixed it, but it was the last set of things I tried (and worked!).

Try the following at your own risk. I have no idea why it worked for me. It just did.

1) Uninstall ALL Apple and Apple related products from the control panel.

2) Reboot and run CCleaner followed by reboot.

3) Install iTunes 9.0

4) Update iTunes 9.0 to the current version by the Help->Check for Updates menu option.

5) Go to the directory C:\Program Files (x86)\Common Files\Apple\ and copy ALL files in \Apple Application Support\ into \Mobile Device Support\.

6) Add "C:\Program Files (x86)\Common Files\Apple\;" (or one of the two mentioned subfolders in step 5) to the SYSTEM PATH in Environment Variables. (Remove the quotes too).

7) Reboot.

8) See if it worked?!?

Now, it seems as though 5 and 6 should be redundant, however, only by doing both was I able to make iTunes work. Strange...

Good luck to others with this issue.
Jeff

<Edited by Host>

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MobileDeviceHelper has stopped working - and will not stop stop-working!

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