update from 3.1.3 to 4.3 software
Last IOS version for iPhone 3G is 4.2.1.
What happens if you plug your iPhone 3G into your version of iTunes?
Does iTunes report that a newer firmware version exists and offers to update it?
When I plug the iphone it recornizes it, and tells me that I have the latest version (3.1.3.)
Retrieving data ...