So ATT unlocked my iPhone, but I had to get it replaced by Apple, but they replaced it with a locked iphone 4. Is there anything I can do? I am no longer a ATT customer so they refuse to unlock it again.
If your phone is locked to AT&T and you were once a customer but no longer, AND you don't owe them money or anything, they will unlock your phone.
Go to their website and read the requirements. Read them to the CS rep on the phone if you have to, then ask for their supervisor if the don't unlock it.
Funny thing just happened. The refurb iPhone 4 wouldn't activate in the Apple Store with my tmobile sim. But right now after activating it with a att sim card i had laying around, I plugged the tmobile sim back in and what do you know, it connected.
I'd have guessed that as unlocking is done on Apple server's, it would recognise the fact when the serial number is replaced (much like when the warranty automatically moves onto a new serial during replacement).
I know it's a bit more stricter with unlocking in the US than the UK so that may be why, but when I had to get my iP4 replaced I checked with the genius and he said it would remain unlocked, despite the fact that all replacement iPhones come out of the same drawer.
The best way to get factory unlocked iPhone 4 is to buy an iPhone 4 from ebay (locked to AT&T) then to use factory unlock service to Unlock your device. Thanks.