I have just installed Snow Leopard 10.6.3. onto my MacBook and now my Iphone 4 is not recognized as a device when I try to sync with Itunes on the MacBook??
You probably need to update to Snow Leopard10.6.8
Click Apple icon top left and click Software Update and keep doing that until it says software is up to date.
That should bring your itunes to the correct version.
Hope this helps,
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