I can't seeing movies on my sansa view

My problem is that I cannot see movies in my sansa view.  Recently I format my sansa view after that I not be able to seeing the movies. I make use of the sansa converter as I do in the past when I add movies with out any problem. But now I also look at inside the movies folder an it appears with format WMP I can listen the sound but I only seeing an icon on the screen. Someone can guide me on the matter, I am not a very good expert the technology, therefore I ask if is possible simple explanations. Thanks for your help.