Updating iOS on unlocked iPhone 3g

[slimsandwich]

Hi all, I have an unlocked iPhone 3g running the 4.2.1 iOS with the 6.15.00 baseband. If I wanted to update the iOS to a newer and recent one, how would I go about doing so?

 

[waldoe]

you wouldn't I believe 4.2.1 is as high as you can go on the 3g.

 

[Thomasjtsi]

you wouldn't I believe 4.2.1 is as high as you can go on the 3g.

This is correct... iOS 4.2.1 is the highest version the iPhone 3G supports. However, if you're simply wishing to do a restore of your iPhone... you'll need to create a custom 4.2.1 IPSW, to "Shift-Restore to via iTunes" using redsn0w or sn0wbreeze to preserve the 6.15.00 iPad BB.