I need to unlock my 3GS after greenpois0n JB on 5.15.04

[mymail3k]

So, I successfully jailbroke my 3GS with GP(I am on 4.2.1, new bootrom). What should i do to unlock it now.

I tried redsn0w 0.9.6b6 to update my baseband to 6.15, but redsn0w crashed in Win 7 32 bit, i ran it as administrator. I got my phone out of DFU mode, but the firmware still shows 5.15.04 I used the iPhone2,1_4.2.1_8C148a_Restore IPSW file.

Am i doing something wrong, any help would be greatly appreciated. Thanks.

[Amadomon]

Yes indeed, you're doing...everything wrong. First of all, ultrasn0w unlocks existing basebands, it doesn't update them, and it doesn't unlock yours yet.

At this point, you'll have to either cook your own 4.2.1 firmware with the iPad baseband or download a similar bundle if you can't/aren't comfortable making your own. Check the numerous guides on this site.

[mymail3k]

i am sorry i meant to say redsn0w not ultrasn0w, i updated my post above.

My question is, will redsn0w be able to update my baseband to 6.15 if i am on 4.2.1

[iPittsburgh]

You are not doing everything wrong. Use redsn0w 0.9.6 rc8 and point it to iPhone2,1_4.2.1_8C148a_Restore when you get to the select options part only select "install iPad baseband", next, make sure iphone is connected to computer and powered off completely, next, follow on-screen directions to enter dfu mode, redsn0w will now install iPad baseband, once your phone reboots, open cydia, search for ultrasn0w 1.2, select install, select confirm, reboot, enjoy unlocked iPhone.