Patent ID: 7925879

Claim:
An information processing unit having an information division recording function in which a file is divided and stored, comprising: a first storage section for storing a first partial file of a file divided, a second storage section for storing a second partial file, a state detection section for checking an operating state of the information processing unit and detecting that the operating state has changed in a specific manner, a control section for performing a lock processing in accordance with the state detected to the second partial file stored on the second storage section when the state detected by the state detection section is determined as a risky state in which unauthorized access can be performed, and an external memory detection section for detecting whether a removable external nonvolatile memory is connected or not, wherein the lock processing includes an erasure processing of a synchronized file and an encryption processing of unsynchronized file, and the synchronized file is a second partial file in the second storage section which has also been stored on a removable external nonvolatile memory, and the unsynchronized file is a second partial file in the second storage section which is not stored on a removable external nonvolatile memory, and when the external memory detection section detects that a nonvolatile memory is connected, the control section copies a second partial file stored on the second storage section but not stored on the nonvilatile memory to the non-volatile memory.