My iPhone was bought from Apple store Norway in August last year (2010). I noticed the problem first time in early November. The phone had been in flight mode for 10 hours while I flew from Houston to Aberdeen. When I came to Aberdeen the phone found no carriers. The problem was still there after I arrived in Norway later the same day (Wireless worked but not GSM/3G). Did not find my home network operator (Telenor). Had to restore the iPhone.
Found later (through Google) that the problem could also be resolved by doing a reboot. This was done by holding down the two buttons (power and action button) until the Apple logo appeared. This restarted something in the phone and it worked again.
The problem did not happen again until early December. And now it happens once a week and I have had it twice in one day. The phone shows “no signal”. If I try to do a manual operator search, no operators are found. I have to “reboot” using the above procedure.
My iPhone ran 4.1 the first time it happended. I upgraded to v4.21 one week after it became available.
Is this a hardware or a software fault ? Will it be corrected in version 4.3, or do I have to send the phone in for a replacement ?