An image forming apparatus includes: a main frame; a developing cartridge including a casing, a storage medium having an electrical contact surface, and developing roller; a photosensitive drum contactable with the developing roller; an electrical connector contactable with the electrical contact surface; a separation mechanism; and a controller configured to communicate with the storage medium via the electrical connector. The separation mechanism is configured to move the casing relative to the main frame in a separating direction in which the developing roller separates from the photosensitive drum. The controller is configured to perform: moving, by controlling the separation mechanism, the casing relative to the main frame in the separating direction; determining, in response to performing the moving, whether communication with the storage medium is established; and outputting, when determining in the determining that the communication with the storage medium is not established, an error.