7. The document processing method according to claim 4 , further comprising a generating step of generating a management table for identifying the second document file and the first document file.
4. A document processing method for importing a first specified document file into a second document file to be edited, comprising: a determination step of determining whether or not security information is added to the first document file; an import control step of importing the first document file with the security information into the second document file in order to generate a third document file, if the determination step determines that the security information is added to the first document file; a receiving step of receiving an instruction for editing the third document file in a unit of a page included in the third document file; an edition control step of, if edit prohibition security information is added to the first document file, permitting editing of the third document file by movement of all pages which are imported from the first document file into the third document file, and prohibiting editing the third document file by editing of each page among the pages imported from the first document file; an adding step of adding additional information to a page based on the first document file; a control step of causing printing based on the additional information added by the adding step; and an export control step of exporting the first document file including the security information from the third document file, wherein the export control step exports the first document file excluding the additional information, wherein the edition control relocates pages of the third document without changing the location of pages in the first document file.