I upgraded to 2.0 stupidly without understanding that 2.0 can not be unlocked. HOwever, I originally used ziPhone to unlock my phone whoch downgraded by bootloader to 3.9. I have managed to restore to 1.1.4 and re-jailbreak, but I have no service.
I have tried each setting of bootnueter stated here but the flash keeps coming back as failed.
Any one know how I can unlock my phone so I can get my service back?
I get the phone into DFU mode and then attempt to restore to 1.1.4. The restore fails with error 1510. However I am able to use iLiberty to kick it out of restore mode and then I am taken to the emergency call screen. The screen with the slie to unlock but will only allow an emergency call. So...I tried to use iLiberty to jailbreak and unlock, which gets me past the emergency screen but no installer and no unlock. I used ZiPhone and this at leasts jailbreaks 1.1.4 but still no unlock, or at least no service.
I think there is a problem with the baseband being the incorrect number for a 1.1.4 restore. I even tried erasing my baseband hoping that a restore to 1.1.4 would install the correct number. Still no service.
I am out of options.....
UPDATE:
My problem is is that the 2.0 upgrade also upgraded my Base Band. I needed a way to downgrade the BB so I could restore 1.1.4. KiPhone is the software I used to do so. Once downgraded, I was able to restore back to 1.1.4 without any errors. I then used ZiPhone to JB/activate/unlock my phone. Once at the springboard, I did a reset of all settings and a quick re-boot, and the AT&T logo was back!!
I can make and receive calls and I feel as though my iPhone is all brand new again

I'm such a sap.
Anyone having the same issues may want to give KiPhone a try.
iClarified - iPhone - How to Downgrade Your Baseband Using KiPhone