Help unbranding Nokia N75

I've searched everywhere, i followed instructions word to word, but its still not working! I changed the product code to a unbranded Nokia N75, but i still can't update. The Nokia Software Updater says my phone is not supported. Any help?
-bubblebuddyi

You need to unlock your phone first. That is why, I had the same problem, phone is plugged in and software downloaded and it checks but no phone is recognized yes? If you have a good standing account with ATT or at least for a few months, you can call them and ask to have it unlocked, i recently did this to my N75 and they sent me my Unlock code really quick in email.. I debranded and it is DEF much better let me tell you..

ahhhh ok thanks. I've been a customer sense like 1999 or earlier.. i don't think i have a problem