Ask a moderator to get your posts/threads deleted or modified. In most forums you need staff privileges to do so. Posts can usually be modified using edit in the right bottom corner, unless there is a rule to prevent it, sometimes applied to the starting post.
Why cant you modify your own posts in this forum, just a question, as im starting up my own forum and just wanted to know what the advantadge would be?
If someone has a problem with one of their posts, user should use the report bad post feature (triangle outlined in red) to request help from a mod. Users can edit their posts for 8 hours. User can delete posts in first eight hours so long as post is not the first post (thread starter) in a thread.
Yes, report the post that you need help with. Mods can be found here: http://forums.digitalpoint.com/showgroups.php