Hi,
I got the same problem but i’m not using mulitsites and i tried:
define( 'FOOTBALLPOOL_RANKING_CALCULATION_NOAJAX', true );
The ranking table in the database is empty and I get the same error at:
$ranking_id = $ranking_ids[$ranking];
What do you guys mean with: I now added an user specified ranking and then it worked!
Did you use something like this:
[fp-user-ranking user=1 text="not ranked"]
That’s not working for me, how can I add an user specified ranking?