What file format is it saved in? What program (latex, pdflatex, etc.) are you using to compile?
Please provide a real
minimal working example. The code you gave certainly isn't right. The \usepackage line needs to go in the preamble, and the \includegraphics line needs to be in the body, so at the least, there needs to be \begin{document} in between them, but posting a complete document is always preferable. See the
Post on Avoidable Mistakes.