Hey folks, Just a quick bit of advice to those who have purchased an iphone (for example on eBay) and later found that its locked to an unknown network and therefore unable to activate it and getting the "sim not supported message". I have spotted lots of online posts regarding how to find out which network its locked to without having official carrier sims to try out in the phone. people have said about model number but this will only give you a region as opposed to the lock status. simply take it into your local apple store and they can look up which network it is locked to. simple as that. Apple belfast were brilliant.