iTunes 7.7 unable to locate dataclass information from Sync Services

Give this a shot:

Go into Control Panel > Programs & Features
Remove these applications:
1. Apple Software Update
2. Apple Mobile Device Support
3. Bonjour
4. iTunes
5. QuickTime

Restart the computer
Download & Install the Windows Installer Cleanup Utility:
http://support.microsoft.com/kb/290301/
Launch the Utility: Start > Programs > Windows Install Clean Up
Select any of the above mentioned applications, and click Remove

Restart the computer again
Download & install iTunes again from here: http://www.apple.com/itunes/download/
Choose the option to "save" the download and save it to your desktop
When the download completes, if it asks you if you want to run the software, say no
Right-click on the iTunes Setup file on your desktop and choose Run as Administrator

CG

So far, you're right on with the steps. It's a good sign if none of the software is listed in the cleanup utility; that generally means it was appropriately removed with the previous step(s). This utility is mainly for some stubborn or damaged programs that won't uninstall via Programs & Features.

I haven't yet seen a definitive fix for this; different options are working for different people.


Some other suggestions:

-Reinstalling the iPod driver
Connect the iPod
Click Start, right-click My Computer and click Manage
Select Device Manager in the left-hand column
Scroll down to Universal Serial Bus controllers in the right-hand column
Click the + next to it to expand it
Right click on the Apple Mobile Device and click Uninstall
Restart the PC with the iPod connected

-Working out a syncing conflict
Do you have other devices that you sync to your computer? Either way, try this:
Close iTunes and disconnect your iPod
Click Start, right-click My Computer and click Manage
Select Services in the left-hand column
Scroll down to Windows Mobile Service, right click it and click "disable"
If disable is not an option choose Stop
Open iTunes and connect the iPod

-Disable any and all firewalls
This may result if the Outlook Sync Server service is blocked
If this resolves the issue, look into configuring that firewall to specifically allow this service.


Keep us posted on what (if anything) works for you
CG

jtd18 wrote:
In regards to "Reinstalling the iPod driver," the Apple Mobile Device was not listed in my Universal Serial Bus controllers.

Was your iPod connected to your PC at the time? Make sure the iPod is connected, and displaying the screen that says "Connected, Eject before disconnecting." Try disconnecting and reconnecting the iPod if you're not seeing that while it's connected.

In regards to "Working out a syncing conflict," the Windows Mobile Service was not listed in my Services.

I'm thinking that might be because there aren't other devices syncing to your PC. Correct me if I am wrong. Did you have any success disabling firewalls?

Also, I'm wondering if you've tried resetting the sync history.
In iTunes, click Edit and go to Preferences
Select the Syncing tab
Click the Reset Sync History button and click OK
See if the error continues.

CG

I've seen this reported on some other threads, really not a lot of good information on them. One post mentioned the author had spoken with Apple's technical support and they indicated it was related to an overloaded iTunes server, due to the new software and app store and whatnot, but I would think that most of that overload has been eased by now. And I'm not 100% convinced on that answer anyway.

CG

Message was edited by: CasperGemini (typos, yikes)

These are the latest two suggestions dug up from some other boards:

Restart the Apple Mobile Device service:
http://support.apple.com/kb/TS1567

Uninstall Microsoft Sync Center, if you have it installed.

I'm not sure I'm leaning so much toward it being a Microsoft issue, because there's nothing even remotely close to this error on Microsoft's knowledge base.

CG

Let's try testing this in a new user account.

1. Go to Control Panel > User Accounts
2. Click on "Manage Another Account"
3. Click on "Create new user"
4. Follow the prompts to create a new computer administrator
5. Restart the PC and log in to the new account

See if you can connect the iPod and make the same error appear. Regardless of the outcome of this test, I'm thinking we should go back to the first link of your first post and contact Apple Care regarding this. There must be a good reason for them to request users with this issue contact Support... perhaps they need information in order to determine the best course of action.

http://www.apple.com/support/contact/

CG

PS. If you do contact a representative and come up with a solution, I'd be interested in hearing what comes of it.