how to post a message on a friends facebook wall facebook c# sdk

using facebook c# sdk, I'm able to post to my wall but when I try to do it on my friend's wall, it just does not show, any ideas why this could be happening?

client开发者_StackOverflow.Post("me/feed", parameters); ----works

client.Post("friends id/feed", parameters);--does not work

or client.Post("/friends id/feed", parameters); --does not work

Make sure the app is not in sandbox mode, or if it is, add that friend as a developer of your application. Also, post the error message you are getting.

Sorry to tell you, but you can't actually do this.
Facebook has change the privacy settings, so that you can't access your friends wall using an app Please find the relevant info here https://developers.facebook.com/roadmap/completed-changes/
(look for the change of February 6th)