? Delete what?
If you are talking about a thread about a problem, we never delete those. Part of our goal is to keep solved problems available for anyone have a similar problem in the future.
If you're talking about a post you have made, you can use the "Remove" button next to the "Quote" and "Modify" buttons.
If you can't delete this particular post, the only one in the thread, that may require an Admin to delete the thread. This software may not allow deleting the only/last post in a thread.