A workflow executing device executes the steps of: specifying a workflow; executing processes defined by the specified workflow; specifying an external process to be processed by a first external device from among the processes; specifying a device that stores account information requested by the first external device as a second external device in order to allow the first external device to execute the external process; generating a sub-workflow that defines a login process of logging into the first external device, a request process of allowing the first external device to execute the external process, and an execution result output process of transmitting the execution result to the workflow executing device; and changing the external process in the workflow to a workflow transmitting process of transmitting the sub-workflow to the second external device and an execution result receiving process of receiving the execution result from the second external device.