I'm having the same problem, although it seems to also alternate between two other errors.
Under Settings › WP-AutoSharePost, the User/App/Page Name and Token fields are greyed out. I assume this is normal until the token is requested?
Here are the error messages I get:
1. No facebook user supplied. Did you give all permissions?
2. Could not find any app associated with this user with appId "".
3. An active access token must be used to query information about the current user.
It seems to 1-2-3, then back to 1 in perpetuity. But all I'm doing is clicking on "Request Facebook Access-Token".
I'm at a loss. Any thoughts?
Thanks and best wishes,
PS - This thread is a month old from the last reply. I have version 0.2.5. This is the newest one, yes? Looking at the github link, I wasn't sure.