Apple Releases iTunes 10.3.1, Potentially Fixing iOS Device Syncing Bug
Just a day after releasing iTunes 10.3 to support some early iCloud features such as automatic downloads and access to previously purchased content, Apple has already pushed out iTunes 10.3.1 via Software Update and the company's software downloads page.
The documentation accompanying the release merely offers the same information as found with the original iTunes 10.3 release, providing no word on exactly what is addressed in what is presumably a minor bug fix update.
A number of users in Apple's support forums and elsewhere have reported issues with syncing iOS devices under iTunes 10.3, with iTunes reporting an "unknown error (-50)" when attempting to sync. Consequently, it seems reasonable to speculate that the iTunes 10.3.1 update addresses this issue, although we have yet to receive confirmation from users.
http://www.macrumors.com/2011/06/08/apple-releases-itunes-10-3-1-potentially-fixing-ios-device-syncing-bug/