A.L.
It means that the person who posted the question decided to delete his/her question afterwards, and the only way to do that is to replace the text with something else, such as a letter or dots. It's actually a somewhat annoying thing to do because other people went to the trouble of typing in answers and once the original question is eliminated, someone else with a similar question can't benefit from those answers. However, that's why you see a few posts like that.