8. A method according to claim 1 , including the following steps before the obtaining step a) which steps are performed by a fourth processor unit: i) obtaining an initial electronic document; j) determining in said initial electronic document the at least one item of sensitive text data that is to be made secure; k) generating the secure data from said at least one item of sensitive text data; and l) processing said initial electronic document in order to obtain the secure electronic document by including in the initial electronic document the at least one marker associated with said secure data, and by deleting or masking the at least one item of sensitive text data.
9. A method according to claim 8 , wherein said processing step l) further comprises including said secure data in the initial electronic document.