The velasco.sis file will not arrive automatically to the target device, so a user needs to answer yes to the transfer question while the infected device is still in range. When the Lasco.A worm is activated, it will start looking for other Bluetooth devices and starts sending infected velasco.sis files to the first device it finds. After the first target phone is out of range, Lasco.A will continue searching and infecting other phones. Keeping a phone's Bluetooth visibility setting in "hidden" will prevent infection.