Hi Ritesh,
I deactivated all plugins accept Buddypress and rtMedia ... Tried on TwentyFourteen. Still getting the same error ...
[Wed Jun 22 09:57:53.823842 2016] [:error] [pid 6628:tid 1636] [client ::1:50288] PHP Fatal error: Cannot use object of type WP_Error as array in C:\xampp\htdocs\wordpress\wp-content\plugins\buddypress-media\app\main\controllers\media\RTMediaMedia.php on line 512, referer: http://localhost/wordpress/members/admin/media/3/ [Wed Jun 22 10:05:15.505745 2016] [:error] [pid 6628:tid 1680] [client ::1:50558] PHP Fatal error: Cannot use object of type WP_Error as array in C:\xampp\htdocs\wordpress\wp-content\plugins\buddypress-media\app\main\controllers\media\RTMediaMedia.php on line 512, referer: http://localhost/wordpress/members/admin/media/8/