You are describing clerk interrupt. This does have special memory allocation to work. It probably means the machine was RAM cleared by one of the technicians (which was what I was recommending). The interrupt memory would need to be re-allocated and the buffers etc would need to be linked for clerks. It is not usually a simple thing and the program may need to backed up again before changing memory. If you want to use it, take it back and get the technician to set it up.