Wanted to share this with everyone, I have an iPhone 4, got it on launch day last year, over the last few days i have had the "NO SIM CARD" message keep popping up toggle airplane mode on off does the job but it keeps doing it, rang o2 got a new sim still same problem, rang them again nice lady told me to go to my nearest Apple store were they would swap it for a new one! i still have 45 days warranty left, rang Apple to book a genius appointment, went today at 2pm 10 mins later got new iPhone, maybe you knew this but i certainty didn't, when i have rang o2 before they told me to sent it back to them blah blah and if it is faulty they would sent me a reconditioned one back would take up to three days,
this way i was back up and running within the hour
nice one o2 and Apple
this way i was back up and running within the hour
nice one o2 and Apple