How do you go about updating to SDK 4.0?

IntelligentDesigner

I tried running the downloaded file but it did not do anything...

CoIin

Remember that there is a risk that you will have to find a way to reset the phone back to an earlier version if v4 goes horribly wrong for you, and that may not be simple to do.

Having said that, I'm enjoying v4 so far! What I did was download and install the 3.1 GB SDK4 software, download the 381 MB iPhone OS disk image file and mounted it on the desktop, then in the Organizer window of XCode I selected my connected iPhone 3GS, and from the Software drop down menu in the Summary tab I selected Other Version... and pointed it to the "iPhone2,1_4.0_8A230m_Restore.ipsw" file on the mounted image. Then I clicked the Restore iPhone button.

Quite a while later the phone wanted me to open Tunes, and in there I chose to restore the phone from the backup that it had. That reinstates your network and other settings. Finally, I synced all the media I wanted back onto the phone.

IntelligentDesigner

Thanks, Colin! You were certainly right about the long period of time it takes...

After you do this, it appears you cannot back up the iPod anymore...

And if you synch, the stuff falls out of the folders back into the springboard. But it is good to see where the OS interface is going.

Cheers!