Upgraded unlocked 2G iPhone to 3.1.2 now its locked - PLEASE HELP!!!

[crazydrvr20]

Hello everybody, I am new to this forum and I am very desperate. I bought an unlocked 2G iPhone running 3.0 which worked fine. Don't ask me why, but when I connected to iTunes, I decided to upgrade to 3.1.2 which caused my phone to get locked. Now all the phone shows is the emergency call screen and all iTunes showes is "The sim card inserted in this iphone is not a valid sim...".

Now, I have tried everything this board has sugested to fix the problem and I can not get the phone to unlock. PLEASE LET ME KNOW WHAT I CAN DO, I NEED MY PHONE!!!! Thnak you for any help...

P.S.: I am runing Windows Vista.

[Daughain]

Ok, dunno about vista, but, when I got that screen, simply hooking to itunes and tinkering with it would eventually get rid of it. Unfortunately, I dont remember what steps I took. I may have had to reinstall 3.12, I just dont remember. I had that issue a number of times till I got blackrain to work. Keep the faith, it will work.

[mrjtang]

easy fix

when the phone is on
1. press and hold power button + home button
2. once the phone is off, release the power button while STILL holding onto the home button.
3. this will put your phone into DFU mode
4. run itunes again to restore your phone to 3.1.2

after thats finished. go to..
blackra1n
download blackra1n software

while the phone is still connected, go ahead and load blackra1n.
click on "make it ra1n".

now you will have access to the springboard on your iphone. turn on your wifi via settings. go back to the home screen and scroll to the last page of programs. load blackra1n. download cydia - thats it!

make some test calls to and from your phone.

your phone should work now

[lennaertdeboer]

A short while ago I had exactly the same problem. I was fixing my friends locked 2G iphone. I restored to iphone firmware update 3.1.2. And just as MrjTang said, I jailbroke my iphone using Blackra1n. The only thing I had to do from there was to enter my wifi acces key and install cydia.

So the method MrJTang wrote should work for you. Thank you MrJtang!

[Daughain]

That DFU thing never did work for me.