User ID File has Certificate Expired

How to re-active the Certificate Date?

Subject: User ID File has Certificate Expired

Refer:http://www-12.lotus.com/ldd/doc/domino_notes/Rnext/help6_admin.nsf/b3266a3c17f9bb7085256b870069c0a9/9e41bd884430d37785256c1d00391fd9?OpenDocument

Litty Joseph