Sorry for this, I actually see now that me problem was from something ells in my app and not what I was thinking it is. Sorry for wasting time
That's it. No explanation, no additional information, nothing. This answer came after a round of edits in the question that may or may have not invalidated the answers already posted - I am not qualified to judge, but there are some complaints in the comments about this, which may have prompted the apology in the last sentence.
What, if anything, should I do in cases like this, where the OP of the question answers with an otherwise useless "sorry, my bad" post?
Flag the answer as "Not an answer"
The "answer" is most certainly not an answer, since apparently there was no question in the first place. At least, it is not an answer that could help future readers solve a similar problem. It also contains no additional information of any kind. On the other hand, it does provide a form of closure to this thread, even if it is an answer of the PICNIC variety.
Vote for the question to be closed
Done, as suggested here - in my opinion, the question wasn't elaborate enough to worth salvaging.
Flag the whole question and ask for deletion
The OP admitted that the problem was elsewhere, which invalidates the question and turns it into noise. In addition, future readers might get misled if they do not notice that final post by the OP. Yet, there are two answers that may be useful to them.
Add a comment asking the OP to delete the question
This was suggested here, but its does have the same potential issues as flagging the whole question - the only thing that changes is who would do the deletion.
Leave it alone
Well, there's always the easy way out :-)