Apple stopped the Update of iPhone3G on V4.2.1
first make sure that you are using original hostfile to avoid error
Check it.
goto my computer/drive C:/windows/system32/drivers/etc./host-
(open with note-pad) delete all the content of your hostfile and
copy all the content of my original hostfile and save it.
PROCEDURE
Open itunes software[You must be registered and logged in to see this image.]Put your Device into
DFU MODEHow To:
[You must be registered and logged in to see this link.]How To:
[You must be registered and logged in to see this link.]This message pop-ups in your computer
Click OK
Hit the SHIFT KEY on your Keyboad together w/
restore button on your screen monitor.
[You must be registered and logged in to see this image.]Browse your IOSW 4.2.1 (3G):
[You must be registered and logged in to see this link.]when its done restoring...
PUT ORIGINAL SIM CARRIER TO ACTIVATE...
connect to itunes and wait for device activation.
Quote:
This Ultrasnow will support baseband
(01.59.00 / 04.26.08 / 05.11.07 / 05.12.01 / 05.13.04 / 06.15.00)
And not compatible with
(02.10.04 / 03.10.01/ 04.10.01 / 05.14.02 / 05.15.04)
Note: if your idevice is FACTORY Unlocked Don't update your baseband...
and you don't have to unlock the idevice..
Another way to Activate Device is Jailbreaking.
JAILBREAKING AND INSTALLING IPAD BASEBAND
Use REDSNOW9.6b6
Open REDSNOW SOFTWARE
[You must be registered and logged in to see this image.]Click BROWSE
[You must be registered and logged in to see this image.]Load IOSW 4.2.1 (3G):
[You must be registered and logged in to see this link.]Wait until IPSW successfully Identified
Click NEXT
[You must be registered and logged in to see this image.][You must be registered and logged in to see this image.]CHECK
Install Cydia
Install iPad Baseband
Enable Battery Percentage
[You must be registered and logged in to see this image.]message will pop-up
just Click OK
and Click NEXT
[You must be registered and logged in to see this image.]Follow REDSNOW Instruction for DFU MODE
Click NEXT
[You must be registered and logged in to see this image.]PROCEDURE OF UNLOCKING
iFunBox V1.5.621.548 [
[You must be registered and logged in to see this link.]]
[You must be registered and logged in to see this link.]idevices v4.1 to 4.2.1
[You must be registered and logged in to see this link.] idevice v4.3++
1. collapse Raw file system
2. open private
3. open var..
4. open root
5. open media
6. open"Cydia"
7. open"AutoInstall"
8. Inside AutoInstall folder,extract or paste the two files you download
for unlocking..
then reboot twice..
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