A system is described for automatically invoking computational resources without intervention or request from a user of the system. The computational resources may operate by searching across a network, or may themselves be located across a network. In the system a query-free information retrieval system is described in which the exact technical documentation contained in existing user or other technical manuals is provided to a user investigating apparatus having a fault. The user enters symptoms based upon the user's analysis of the apparatus, and in response the system provides information concerning likely faults with the apparatus. As the symptoms are entered, to relative value of individual faults is determined and related to the symptoms they cause. The user can then select technical information relating to probable faults in the system.