Sometimes phones cut off users while they're speaking. Resetting the phone can help restoring the phone's settings. Before opting for a reset, the data stored on the phone should be backed up, as it will be deleted and impossible to restore. This article gives two methods of resetting Nokia cell phones to their factory settings: the Normal and the Deep reset. Resetting in Normal mode uses a different combination of key sequences from Deep mode. This article also highlights the need to create a data backup as resetting will delete data from the phone memory.
When using Symbian60 v1 based phones like Nokia 7650, 3650 or Ngage models, these two key sequences should be entered in the same way you dial a phone number.
On the S60 phones, you should try a Deep Reset, using the following steps: