try {
List<PlugInInfo> knownPlugIns = IOObject.readList(configFile) ;
// Plug-in is unknown
if (!knownPlugIns.contains(info)) {
throw new UnknownPlugInException(info) ;
}// if
// Remove plug-in info and save the result
knownPlugIns.remove(info) ;
IOObject.writeObjectToFile(configFile, knownPlugIns) ;