Users on Apple's discussion board have been experiencing issues with their PCs locking out iPhones when using Windows 7 with the Intel P55 USB chipset. It's a pretty specific combo that you're probably not running, so don't panic.
The thread is only five pages long, but multiple users are claiming the exact same "0xE8000065" error message when trying to sync their data. The issue appears on P55-based motherboards from Asus, MSI and Gigabyte, and it seems like Windows 7 64-bit is more prone to the problem than its 32-bit brother.
Keep in mind the P55 is a new chipset, and unless you're computer is brand-spankin' new or you're the DIY type, chances are you have a setup that works perfectly fine.