I am having the same issue on random pinterest accounts, i do have the right to post on these boards so it seems just an API problem.
Array ( [pgID] => [isPosted] => 0 [pDate] => 2014-06-03 09:34:17 [Error] => Something went wrong – Array ( [api_error_code] => 7 [message] => You don’t have permission to edit that board. [code] => API_ERROR [target] => [http_status] => 401 ) )
