Signed IPSW files can be restored via iTunes. Unsigned IPSWs cannot currently be restored via iTunes.
✗ | iPhone 4 (GSM) | iOS 4.0.1 (8A306) | 13th July 2010 | 607 MB | iPhone3,1_4.0.1_8A306_Restore.ipsw |
✗ | iPhone 3G[S] | iOS 4.0.1 (8A306) | 13th July 2010 | 396 MB | iPhone2,1_4.0.1_8A306_Restore.ipsw |
✗ | iPhone 3G | iOS 4.0.1 (8A306) | 13th July 2010 | 320 MB | iPhone1,2_4.0.1_8A306_Restore.ipsw |