Can't unlock a previously unlocked AT&T SIM (business account)

[Lulu]

I'd successfully unlocked the iPhone and was using my AT&T SIM from a business account. After having done the upgrade to 1.1.1, the SIM is unlockable.

The method I used was: Restored to 1.0.2, then upgraded to 1.1.1, using directions on hacktheiphone.com > Start Here > Deprectated Steps. When that did not work I restored to 1.1.1, and tried to unlock via hacktheiphone.com > Start Here > Step 1.

AnySIM gives a message "AnySIM could not unlock this phone." To unlock 1.0.2 I use a combination of apps such as Cyberduck, Independence, lockdownd and others. The question is: What unlock method is suggested for an AT&T SIM?

Thanks,
Lu

[*iphoneGod]

dude if you did the steps right it should unlock perfectly, but this is what you need to do all over again.... Restore , Virginize it then do the depriated Step on 1.1.1 to 1.0.2 then back up to 1.1.1
You just screwed up your bandbase and its so corrupted right now. Your At & t sims should work fine now, or you could buy Iphonesimsfree software and granteed unlocked, as it doesnt screw with the bandbase but use's your IMEI number instead...

[Lulu]

Do you mean do the downgrade, virginize and upgrade (all three) OR use the iphoneSIMfree in place of those three? Or do you mean downgrade, viriginize and then choose to either upgrade or use iphoneSIMfree?

[Kenal0]

I am using an ATT business sim as well. I was under the impression that unlocking is not necessary, just activating with Independance after jailbreaking with deprecated instructions. Why the need to unlock if you are using an ATT sim?
I use my Blackberry sim card. The unlimited Blackberry data plan covers the data usage on the iphone.
Check this out, seems to be similar to your problem.
Imei of death article
http://www.hacktheiphone.com/111/iphone_information_1.html