Best thing to do
Step 1, download and install kies
(not kies mini)
step 2, pull your battery and write down your S/N (not your IMEI number but the serial number)
step 3, start kies and then turn the phone on and go into download mode (hold volume down, when prompted press volume up)
step 4, let the drivers install
step 5, once all that is done, in kies, Choose Tools
, Firmware upgrade & initialization
a) While in download mode, enter the S/N & model name (ALL CAPS!! SGH-I717 not SGH-i717)
b) It will prompt to initialize to original settings. Click "YES"
c) It will prompt to initialize the latest version. Click "YES"
d) It will download the firmware upgrade components (DO NOT DISCONNECT THE DEVICE!!)
Setp 7, Kies will prompt for firmware upgrade and initialization.
a) Click check box for reading above information
b) Click your choice if you want your information saved on Samsung Kies corporate servers (I choose WITHOUT
Now walk away from your phone for 15-20 minutes. When you get back your phone will be 100% stock and on the official ICS
Original credit for this here: http://forum.xda-developers.com/showthread.php?t=1731654
If you want to go back to GB, it is a longer process, but PM me and I'll walk you through it.