some boards, you can edit years later (I have-on ProBoards) others like PHP (this one) Invision or Zeta, have time limits that I believe are set by the admin of the board. I got into trouble (can you imagine that) on an Invision forum, and my ability to edit was completly taken away. I don't go to that place any more. they were all kind of off the wall. I was always out of step.