I received that error every time I started iTunes for a couple weeks. A lot of online help pointed to problems with Sync Services itself however none offered any solution that worked. For me, the solution was to “Repair Microsoft Office Installation“. After that, it worked. If you’ve found this web page after searching for a solution, try that and see if it works.

The new version of iPhone firmware is out. Don’t upgrade if you are jailbroken and/or unlocked as this will probably lock you out until it’s cracked by the “iPhone Dev Team”. Use iTunes to get the latest update if you have a legit phone.