Fuji Xerox has developed an expert system written in InterLisp-D for on-line fault diagnosis of the 1500 J-STAR workstations on the network that connects its offices around the country: when a fault occurs, the user responds to questions from the central system installed in Tokyo on a Xerox 1121 workstation, and the fix is transmitted by electronic mail; the system has a 500-rule knowledge base and is said to cope with 45% of snags.