You are able to rest a Series 40 phone. Formatting is called ‘refurbish‘ and that can be done by tools, officially only available to Nokia Care Centres. Normally, these centres do not alter the memory card content (although they could).
The Soft Reset thru' *#7370# seems to work on some of the recent S40 series Phones. You may try dialling the code and when prompted enter the Security code which is 12345 by default unless changed by you ..If it works, only the data in Phone memory will get erased ...
06-11-2013 13:18 - edited 06-11-2013 13:20
Which is ‘just’ a software reset. Although *#7370# is quite complete, it is nothing compared to a hardware reset (format) like with Symbian phones (for example, certificate authorities are not restored). Only a refurbish does this in Series 40 land.