The 'No SIM Found' is misleading error. when using the unit, I get this msg, then after turning it off and on, sometimes several times, sometimes ejecting and re-inserting the SIM it just starts working. Sometimes the unit works fine for days on end, but sometimes it just won't connect, and I have tried it with three different SIM cards. Sometimes it won't connect with a particular SIM, but then I try the same SIM in a laptop and it's fine. Is there any logfile anywhere which shows the reason for a disconnection or a non-connection. It's infuriating when this happens.