Since Updating our Snow Leopard 10.6.8-based Macbooks to "iTunes 10.7" (& subsequent releases, including iTunes 11 and iTunes 11.0.1), I experienced an issue with the USB "Personal Hotspot" feature provided by the iPhone 4 iOS 6 and 6.1.
When I connect the iPhone 4 through the USB Cable to the Apple Macbook Pro (as above specified), the USB Personal Hotspot feature is not available and our Consultants cannot get to the Internet.
By reading through an infinite amount of Apple Support Community threads regarding the issue (just search "iphone 4 usb tethering" on Google), I was able to determine that the "AppleUSBEthernetHost.kext" provided by iTunes 10.7, 11 & 11.0.1 is defective and doesn't allow the above feature to work.
By Uninstalling iTunes 11.0.1 and manually installing iTunes 10.6.3 (ie. downgrading), the iPhone 4 USB Personal Hotspot Feature is successfully restored.
Unfortunately, by so doing, the iTunes Library is Reset and iTunes 10.6.3 gives an error message at start which says:"An unknown error occurred -42408".
Could you please fix this Critical BUG ASAP?!
Pro, Mac OS X (10.6.8), iTunes 10.7, 11 and 11.0.1