Nokia N80 IE

My Nokia N80 Internet Edition phone started to give me trouble today. The phone mysteriously say that there is No SIM card in the phone and insist that I insert a SIM card.

My first reaction is to "reboot" the phone by powering off and on. That seem to rectify the problem - or at least I thought it did. Moments later when I wanted to use the phone, it again showed the same "Insert SIM card" message. I was annoyed, and hence not over power off the phone, but removed the battery and SIM card, and re-assemble them back together again.
This time, the power up looks ok again and I thought the problem is resolved once again - perhaps a loose SIM?

Another 20mins later when I wanted to use the phone again, the same error occurred. I'm really annoyed now - I repower the phone and it appears ok again. When I went home, and was looking at the phone, it mysterously rebooted - and after rebooting, it says no SIM again. I rebooted a few times and the problem is resolved temporarily.

I've just backed-up the data on the phone (just in case), and then re-flashed the Firmware even though I've already got the latest firmware V 5.0719.0.2 dated 24 May 2007 RM-92.
I'll give further updates is the phone continues to give problem. To check your firmware, just key in *#0000# code.