At the time of a maintenance work, a user computing machine does not give user data to a person (maintainer) who carries out maintenance and does not accept operations and data that are not relevant to the maintenance work so as to prevent the leakage of user data. Specifically, a user computing machine includes: a user data determination section determining whether a file of a VM of a computing machine used by a user is data created by the user, and a VM copy section, creating a copy of a VM which does not include data created by the user by calling the user data determination section. The maintenance is performed by supplying the VM which does not include data created by the user to a computing machine of the maintainer.