An image forming apparatus includes a communicating unit (123) that performs communication with an external apparatus (200), a recording unit (97) that stores image information, an image processing unit (96) that performs image processing, and a control unit (91) that performs control to secure the image processing unit from the external apparatus via the communicating unit, when a request signal for performing processing of the image information is received, if the image processing unit can be secured, convert a file format by expanding the image information and compressing the image information again using the image processing unit secured and transfer the image information converted via the communicating unit, and, if the image processing unit cannot be secured, transmit an indication that the image processing unit cannot be secured and the image information before the conversion to the external apparatus via the communicating unit.