* Tom Riddle (Lord Voldemort) opened the Chamber of Secrets for the first time in 1943, when he was a student at Hogwarts.
* He did it again in 1992, and Harry Potter was framed for it.
* Ginny Weasley, who was possessed by a diary belonging to Riddle, opened the Chamber in 1992.
While Harry did play a pivotal role in stopping the threat posed by the Chamber, he never actually opened it.