Hi Guys, I have a Nokia 8600 which i got last year on contract, it's GSM which means it should be open. My contract is on orange but until recently i have been able to put my tmobile and o2 sim cards in there without any problems. Now it asks for a security code. I cancelled my orange contract and they sent me a pay n go sim card but even though its the same network as my contract it is still askin for a security code. Why is this and how can i change it.
