Engadget found out that Apple's new iPhone isn't compatible with 64-bit versions of Windows XP or Windows Vista.
Struggling with your new iPhone on a 64-bit Windows Vista or XP system? Take solace, you're not alone. The error message, "The software required for iPhone is not installed. Run the iTunes installer to remove iTunes, then install iTunes again." is Apple's magical way of telling you that iTunes is not supported on 64-bit flavors of Microsoft's operating systems. Yeah, we agree, they should have listed the incompatibility on the iPhone specs page under Windows System Requirements. Unfortunately for those of you new to Apple software, it's buried in support article 301301 which states, "iTunes is currently not supported in Windows XP Professional x64 Edition or any 64-bit edition of Windows Vista." Now you know.