Generate “never-expire” access token for Facebook Page

Question

I have managed to post to Facebook Page via API (C#), but when administrator of the page logs out, the following error occurs:

\"(OAuthException - #190) Error valida

Answer 1

Using Facebook API v3.1 - None of the answers above worked for me. Instead, I had to:

1) Create a "system user"

2) Grant him access to the properties I needed (in my case an App)

3) Generate a new token for that app and system user

The instructions I used can be found here