>I attached th lyx message, I can't have a pdf output. What's the problem?
It is difficult to answer your question without more information. Usually this problem occures when LaTeX do not make a pdf file at all. One example of what can produce this problem is the accidental deletion of frame-end on the last frame in a beamer-presentation. However, there are many more... So include information on the document class, what elements are included in your document, and what you are trying to do. And any other information you think may be relevant :). Ingar
