An image processing apparatus including a transmission function for transmitting an image sets whether to permit use of a destination not previously registered. The image processing apparatus also receives, from an external apparatus, data including at least a destination field. The image processing apparatus sets the transmission destination based on destination information included in the destination field of the received data upon a condition that a setting is set permitting use of a previously un-registered destination and does not set the transmission destination based on the destination information included in the destination field of the received data upon a condition that a setting is set prohibiting use of a previously un-registered destination.