Need help on updating 4.1 to newest version ?

Hi guys,I have an iphone 3gs that's jailbroke on 4.1 ipad I believe.
I bought it on ebay & want to take the jailbreak off the phone so I can use facebook & it's apps.
I don't actually know the original carrier,but I have 5 new Sim cards to test the phone once I choose the upgrade option using iTunes.

Will it be ok for me to accept the update as I'm not sure if it will brick the phone or just ask me to Activate the phone using the correct Sim card :-.

Any help more than welcome thanks.

Comments

  • I've since just gone ahead & done a full reset on the iphone & all I'm getting now is the apple logo :-/
    The iphone also is not showing up in iTunes now or in device manager.........

    Anyone know what else i should try /