A remote server identifies based on unique identification information, model information, operator name information and/or owner name information, and a plurality of pieces of contact information. The remote server identifies trouble content information, estimated cause information, and seriousness information based on trouble content identification information. The remote server simultaneously transmits transmission information to contact addresses indicated by the plurality of pieces of contact information identified, the transmission information including the model information, the operator name information and/or the owner name information, date and time information, position information, the trouble content information, the estimated cause information, and the seriousness information. When the seriousness information has a highest rank, the remote server adds instruction information instructing a phone call to the operator and/or the owner to the transmission information to be transmitted to the contact addresses indicated by the plurality of pieces of contact information.