"Unable to load data class information from sync services" alert message in iTunes for Windows
Symptoms
You may see the following message in iTunes when connecting an iPhone or iPod touch to your Windows computer or when trying to sync with your device:
"iTunes was unable to load data class information from sync services"
Products Affected
iPhone, iPod touch, Windows 7, iTunes 9 for Windows, Windows Vista, Windows XP, iTunes 8 for Windows
Resolution
Solution 1
Ensure that you have updated to the latest version of iTunes.
Solution 2
Outdated versions of Symantec Endpoint Protection may cause this issue. If Symantec Endpoint Protection is installed on your system, confirm that it has been updated to Manufacturer Release 3 or later.
Solution 3
If you have third-party Bricopacks like Vista Ultimate Inspirat 2 installed on this system, remove them to resolve this issue.
This document will be updated as more information becomes available.
Important: Mention of third-party websites and products is for informational purposes only and constitutes neither an endorsement nor a recommendation. Apple assumes no responsibility with regard to the selection, performance or use of information or products found at third-party websites. Apple provides this only as a convenience to our users. Apple has not tested the information found on these sites and makes no representations regarding its accuracy or reliability. There are risks inherent in the use of any information or products found on the Internet, and Apple assumes no responsibility in this regard. Please understand that a third-party site is independent from Apple and that Apple has no control over the content on that website. Please contact the vendor for additional information.