Most people who answer questions here, Ncis, return to them to see whether there has been any reaction, either from the questioner or from other users. So, in order to thank someone whose answer has helped, all you have to do is put a thank-you comment right there. In other words, you can post an 'answer' in your own question-thread, just as anyone else can. In that way, you can be virtually certain that the person concerned will see it.
Welcome to AnswerBank, too.