Users have been reporting of a problem whereby Symbian Anna on the Nokia N8, reboots itself. Normally the first blame would be the software but it also can be the SIM Card, many users have mentioned that with a new SIM card – a problem disappears. One of the solutions is that you can switch the network to GSM but it is recommended that you first re-install Anna.
If the problem still persists then visit the Nokia Care Center for a flash, this should solve the issue. But if the problem does carry on, then only change the SIM card.
With personal experience, it isn’t recommended that you perform the flash by yourself no matter how good you are, for safety purposes – it would be better if you do let the software technician do the flash for you.
An experienced Nokia N8 user said that the Nokia N8 devices do get less tolerant of the old SIM Card.