[Casterina]

I've a Blackberry 8520 on contract for two year expiring this September, I've used the contract sim card on my iPhone and I want to sell the Blackberry 8520, how do I erase all data, BBM messages and contacts?

Also since the Blackberry 8520 is on contract, can the buyer check my information such as name, address and others?

[Ben1232]

Just incase you change your mind, perform a full back up on BlackBerry desktop manager first.

Perform a security wipe within options which reverts the phone back to factory settings.