A virtual execution device includes a hardware processor, the hardware processor forming a virtual device by simulating an image forming apparatus in operation, in the case where a predetermined allowing condition is unsatisfied by an operation state of the image forming apparatus, acquiring a plurality of respective jobs that have been externally received by the image forming apparatus before the allowing condition becomes unsatisfied by the operation state of the image forming apparatus as reference jobs, selecting one or more reference jobs as exclusion jobs from among the plurality of acquired reference jobs, causing the virtual device to process subject jobs that are not the one or more selected exclusion jobs among the plurality of acquired reference jobs, and in the case where the allowing condition is satisfied by an operation state of the virtual device, specifying the exclusion jobs as cause jobs that have caused errors in the image forming apparatus.