Facebook Long Live Access Token Post from App to Page

How to get a long live access token.

Goto the page graph explorer and generate a short live access token with extended permissions publish_stream and manage_pages rights

Give permission in the popup box

copy the app_id, app_secret and access_token in the following url:

https://graph.facebook.com/oauth/access_token?             
    client_id=APP_ID&
    client_secret=APP_SECRET&
    grant_type=fb_exchange_token&
    fb_exchange_token=EXISTING_ACCESS_TOKEN 

and get the long lived access token.

Now open https://graph.facebook.com/me/accounts?access_token=<long lived token>

now copy the access_token from the page you want.

Happy posting for about 60 days..