Signed IPSW files can be restored via Finder, the Apple Devices app, iTunes, or idevicerestore. Unsigned IPSWs cannot currently be restored to.
Signed IPSWs
| ✓ | iOS 4.2.1 (8C148) | November 18, 2010 | 347 MiB | iPod2,1_4.2.1_8C148_Restore.ipsw |
| ✓ | iOS 4.1 (8B117) | September 3, 2010 | 332 MiB | iPod2,1_4.1_8B117_Restore.ipsw |
Unsigned IPSWs
| ✗ | iOS 4.0.2 (8A400) | August 9, 2010 | 328 MiB | iPod2,1_4.0.2_8A400_Restore.ipsw |
| ✗ | iOS 4.0 (8A293) | June 17, 2010 | 315 MiB | iPod2,1_4.0_8A293_Restore.ipsw |
| ✗ | iPhoneOS 2.2.1 (5H11a) | January 22, 2009 | 278 MiB | iPod2,1_2.2.1_5H11a_Restore.ipsw |
| ✗ | iPhoneOS 2.2 (5G77a) | November 17, 2008 | 278 MiB | iPod2,1_2.2_5G77a_Restore.ipsw |
| ✗ | iPhoneOS 2.1.1 (5F138) | September 5, 2008 | 269 MiB | iPod2,1_2.1.1_5F138_Restore.ipsw |