Abstract: Ensuring that a user obtains a correct version of a file, wherein the file includes a file header section and a data section, is disclosed. Expiration information is inserted in the file header by a first application. The expiration information is extracted from the file header by a second application. An expiration date for the file is determined from the extracted expiration information. The determined expiration date is compared with a comparison date, and use of the file is disallowed if the comparison determines that the file has expired.

Abstract: Ensuring that a file originating on a first computer running a first application, and having a file header section and a data section, is stored in a proper location on a second computer is disclosed. Storage location information is extracted from the file header and a storage location on the second computer is determined based on the extracted storage location information. The storage location information is inserted in the file header by the first application and the storage location information is extracted by the second computer.

Abstract: A viewing configuration is determined for a data portion of a first computer file according to a first view state. The viewing configuration has a parameter, and the first view state includes a first value corresponding to the parameter. The content of the first data portion of the first computer file is presented to a display device based on the viewing configuration. In response to a user request, the presenting is manipulated corresponding to another viewing configuration having the parameter. A second view state is captured from the another viewing configuration. The second view state includes a second value corresponding to the parameter of the another viewing configuration. A second header portion and a second data portion of a second computer file are created.