cant jailbreak ! is it a brick??

[cgcalder]

i bought a 3g off criagslist 3 days ago and been trying to jailbreak since. i have jailbroken several 2g's successfully but don't understand why i cant get the 3g to work. what i've done so far: tried to download 4.0, i tunes says "insert a valid sim card with no pin lock"i cannot find a way uplaod any firmware to the phone. please help, what gives??

[Captinsmooth]

What are you trying to Jb it with? You should be able to use the newest version of redsnow to jailbreak and hacktivate it.

[cgcalder]

tried to use use redsnow to jailbreak for firmware 4.0 but i cant even get firmware 4.0 on the i phone. i tunes just keep saying "need a sim card to activate with no pin lock" i don't if this changes anything but i will be using my tmobile sim card once this gets unlocked.

[BenderRodriguez]

tried to use use redsnow to jailbreak for firmware 4.0 but i cant even get firmware 4.0 on the i phone. i tunes just keep saying "need a sim card to activate with no pin lock" i don't if this changes anything but i will be using my tmobile sim card once this gets unlocked.

Turn the iPhone off plug the cable into the computer then hold the home button while inserting in the cable to the iPhone, now your in DFU and u should be able to install a firmware

[iYeow]

Download your firmware from here:
iClarified - iPhone - Where To Download iPhone Firmware Files From
You cannot restore to stock 4.0 if you don't have shsh blogs.
However, if you want to jailbreak and unlock at 4.1. You have to restore to 3.1.2 and jailbreak it with Redsn0w and then restore to Custom Firmware 4.1. Once you are jailbroken at 4.1, you can unlock with Ultrasn0w. This is just a guide for you to go. I have skiped minor details which I think you can figure out.

[bellyfrog]

Well you haven't said which firmware is on the phone at the moment so it's kinda hard to help.

You need to jailbreak using whatever method is best for your current firmware. Search for "jailbreak iphone 3g x.x.x" (x.x.x being your firmware version) on google and preferably do a redsn0w jailbreak on that version.

Then download snowbreeze/pwnagetool depending if you're pc/mac and download 3G 4.0 firmware. Then cook up the custom 4.0 firmware and restore to it. Again you can find the guide easily by googling "jailbreak 3g 4.0 snowbreeze".

If you don't know what firmware you are running, there may be a program that will tell you (I don't know). Other than that you need to get a SIM card from whichever carrier the phone is locked to or a Phone Book SIM Card to get into the home screen and check the version from there.

Good luck