If you get any sim invalid error message while inserting your fido sim on Rogers based Blackberry phone means,Your mobile is locked by fido.So you will need to unlock your phone.For unlocking you can approach your service provider or else try to buy an unlocking service from any one of the online unlocking service provider like WickedUnlock.com Here you can unlock your phone at low cost.Once unlock your phone,you will be able to use your fido sim card.