Hi James,
Try making it so all the page links appear as so
http://localhost/clients/win/category/listings/photographers?paged=%page%
get_query_var('paged') ? get_query_var('paged') : 1
This part of the code is checking for the paged variable within the WP_Query class, which is essentially $_GET[‘paged’] (and maybe $_POST[‘paged’]), so because the variable isn’t set, it’s defaulting to 1 which is why the first page works, but the rest of the pages are being parsed by WP as part of the post URL.