For some reason my iphone 4 keep going to simm not installed for no reason and it keep going to called failed and sometime people cant call me. this all started after the 7.0.3 update and i tryed to reset settings and its still doing it anyone?
Sounds like a hardware problem. Try removing and cleaning the SIM with a pencil eraser.
i tryed that,(cleaning it) my wifes iphone 4 is also doing that. little more info when you turn it off and back on the problem goes away for 4 hours and then returns
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