1. A method for matching solved cases to a new problem in a case-based reasoning system, comprising the steps of: (a) storing case data for a plurality of solved cases in a solved case database, the case data comprising a set of attributes and attribute values for each of the solved cases; (b) storing component data for a plurality of apparatus in a domain database, the component data comprising a plurality of attributes; (c) storing configuration data for a plurality of identified apparatus in a configuration database, the configuration data comprising indicators for the components that are not part of each of the identified apparatus; (d) prompting the user to select a problem apparatus from the plurality of identified apparatus stored in the configuration database; (e) creating a relevant attributes list comprising all of the attributes in the selected problem apparatus; and (f) creating a subset of solved cases by filtering from the solved case database, any solved case that contains an attribute not in the relevant attributes list.