I just ran into that issue and gave up looking for the answer on the web. So I carried my little Droid down to my friendly Verizon store and asked them. As it turns out the missed call feature is something that only a Verizon rep can change. It is in their system and not in the phone itself. She went into my account and made the change. I asked if it was something I could have done in MyVerizon account online and she said no, it is a program feature of their system.