Navigation menu disapears when I add securityTrimming

  I hope someone can help I've done two tutorials theirs works but when I add this to my site
my nav menu completely disapears. I have roles enabled that works fine I want to hide the admin links. I followed the examples to a tee
I even pasted theirs in and it still wil not work can anyone see what I'm doing wrong
thanks
 

  <roleManager enabled="true" defaultProvider="xxxxx" cacheRolesInCookie="true"   createPersistentCookie="false" cookieProtection="All" >
   <providers
<add name="xxxxx" type="System.web.Security.SqlRoleProvider" applicationName="xxxx" connectionStringName="xxxxxx"/>
   </providers>
  </roleManager>

   <siteMap defaultProvider="MySiteMapProvider" >
    ...