I have an open question on Stack Overflow. It has no answers, not even a comment.
What should I do with it? Delete it or answer it myself? At the Danish "ExpertExchange" the procedure is to answer the question yourself.
If you have the answer, you should definitely answer it. It's encouraged on SO.
You can edit the question with more information, or to word it better and it will bump the question on the Active page.
You can add a bounty to put it on the featured page and draw interest, this is a very effective technique.