Sunday, August 15, 2010

recover from accidentally upgraded Iphone iOS 4.0.2

In case accidentally "upgrade" Iphone4 to iOS 4.0.2, use following procedure to recover it back to 4.0.1.

a) download iOS 4.0.1 from
b) power-off phone, plug to PC, press and hold "home"+"power" till iTune recognizes it
c) select iOS 4.0.1 file with "shift" key on PC keyboard
d) iTune will verify the firmware and and recover iphone4 with it

Wa La~ you are all set~

1 comment:

Yulin Chang said...

Apple already blocked the SHSH for 4.0.1. In case there is no 4.0.1 SHSH backup previously (via Cydia or locally), there is no way to downgrade.