1. A method for a computer or information appliance to securely manage file updates, the method comprising computer-executed steps of: a first processing environment retrieving a bootable disk image for a second processing environment from one of a plurality of data storages in the first processing environment; the first processing environment sending the retrieved bootable disk image to the second processing environment through a first interface between the first and second processing environments; the second processing environment storing the bootable disk image in a first temporary data storage in the second processing environment; the second processing environment initiating a booting of the second processing environment using the stored bootable disk image; following the completion of the booting of the second processing environment, the first processing environment limiting file requests by the second processing environment to the plurality of data storages in the first processing environment through the first interface to only requests required to complete the booting; and the first processing environment managing non-booting requests by the second processing environment to the plurality of data storages through a second interface between the first and second processing environments, wherein the managing the non-booting request including file system requests from the second processing environment comprises: providing to the second processing environment a file system in the bootable disk image supplied by the first processing environment; storing the file system in a second temporary data storage in the second processing environment; upon receiving a request from the first processing environment to process data in the file system in the second processing environment, processing the request on the second temporary data storage in the second processing environment and providing output of the processed request to the first processing environment through the second interface.