If your Symbian mobile phone is very slow type *#7370# and then device will ask you for a security/lock code.Enter your security code Default code is 12345. and then your device will restart and reset.
Make sure your phone is fully charged.Backup must be performed before attempting to format the phone as all the data currently on it will be deleted as a result of the format operation
This method completely formats the phone memory(c: drive). All the user information will be deleted. Like images, music files, installed applications etc. Hence, the phone is set to the default factory settings.
Data stored on E: drive (memory card) will not be affected by these sequences.
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