I have answered a question and the answer has been accepted. I have later seen that my answer was wrong. Problem is that I am not able to delete it.
The question is: type mismatch runtime error 13 access 2007
How is it possible to fix this?
Under normal circumstances, the easiest way would be for you to edit your answer to make it correct, perhaps explaining why your prior answer was incorrect, and what makes the corrections valid.
However, in this case, I wouldn't recommend it, since there is a correct answer underneath yours, and you'll probably get downvoted into oblivion for essentially stealing an answer.
So, what I'd recommend is what the others have: Comment on it to nudge the OP into unaccepting yours (thus removing the 15 rep you gained) and accepting the correct one. Once that's done, you'll be able to delete your answer. If the OP doesn't change it in a day or so, then go ahead and flag for mod attention, noting that you'd like it deleted because it's wrong.