Uncaught Error: Object of class WP_Error could not be converted to string
in /home/alliedbrains/aao.ne.jp/public_html/wp-content/themes/aao/category.php on line 17

Call stack:

1. include()
   wp-includes/template-loader.php:106
2. require_once('/home/alliedbrains/a.../template-loader.php')
   wp-blog-header.php:19
3. require('/home/alliedbrains/a...l/wp-blog-header.php')
   index.php:17