500 Internal Server Error when use UrlRewriteModule

hi
i use UrlRewriter in my web site when run at local it's correct but in server i get error:
the error:
39: <httpModules> 40: <add name="UrlRewriteModule" type="UrlRewritingNet.Web.UrlRewriteModule, UrlRewritingNet.UrlRewriter" /> 41: </httpModules> --- ...