You asked me to:
Does this problem still occur? If so, get in touch with our support team on http://support.wysija.com
I did but I now find an answer here and no replies there.
Ben. Please make up your mind. Here or there?
Anyway I repost my answer:
As soon as we reactivated (after replacing with the new config) we got, at /wp-admin/error_log :
[23-Feb-2013 16:26:19] Error Table .....UPDATE wp_3_wysija_user as A LEFT JOIN artof35_3_users as B on A.email=B.user_email SET A.wpuser_id = B.ID WHERE A.wpuser_id=0 από activate_plugin, do_action('activate_wysija-newsletters/index.php'), call_user_func_array, WYSIJA::activate, WYSIJA_help_user->synchList, WYSIJA_help_user->cleanWordpressUsersList, WYSIJA_model->query
Funny thing about it is that there is the same error twice!!! Produced the exact same second