If you are sending from AOL the problem is probably AOL. Sometimes they don't send and sometimes they block reception of mails from other domains. You will not get a notice from them telling you that they are blanket-blocking, they just do it.
If the address is "BTL" you could be having delivery problems due to BTL, which is not so hot either.
Try again and don't forget that you can call - it's not such an expensive thing to do, and the personal contact may be helpful.