Χρήσιμο blog post: http://blogs.msdn.com/netcfteam/archive/2007/02/01/why-your-netcf-apps-fail-to-call-some-web-services.aspx
Διαβάστε και αυτό: http://blogs.msdn.com/andrewarnottms/archive/2007/07/02/how-to-write-an-especially-precarious-app-on-net-compact-framework.aspx (από τον ίδιο)