How to install:
Unzip the file you downloaded then:
1.- Open iTunes
2.- Connect your iPhone
3.- Sync it (it will do the backup automatically)
4.- Press and hold the ctrl key (alt if you're on a mac) and click the Update button
5.- Select the IPSW file that you just downloaded
Your upgrade should be done in about 10-15 minutes.
Downloads:
iPhone 2G 3.1 Final - iPhone1,1_3.1_7C144_Restore.ipsw
iPhone 3G 3.1 Final - iPhone1,2_3.1_7C144_Restore.ipsw
iPhone 3GS 3.1 Final - iPhone2,1_3.1_7C144_Restore.ipsw
iPod Touch 1G 3.1 Final - iPod1,1_3.1.1_7C145_Restore.ipsw
iPod Touch 2G 3.1 Final - iPod2,1_3.1.1_7C145_Restore.ipsw
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