error when new post after upgrading

I just upgraded to the latest version of WP and now when I try to add a new post under New=>Post, I get this fatal error. How do I Fix?

Fatal error: Uncaught exception ‘Indextank_Exception_HttpException’ in /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-content/plugins/indextank/Indextank/Api.php:101 Stack trace: #0 /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-content/plugins/indextank/Indextank/Index.php(219): Indextank_Api->api_call(‘DELETE’, ‘https://:nob3asv…’, Array) #1 /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-content/plugins/indextank/indextank_search.php(158): Indextank_Index->delete_document(‘318’) #2 [internal function]: indextank_delete_post(‘318’) #3 /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-includes/plugin.php(405): call_user_func_array(‘indextank_delet…’, Array) #4 /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-includes/post.php(2033): do_action(‘delete_post’, ‘318’) #5 /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-admin/includes/post.php(421): wp_delete_post(‘318’, true) #6 /nfs/c08/h01/mnt/118256/dom in /nfs/c08/h01/mnt/118256/domains/inspired-evolution.com/html/blog/wp-content/plugins/indextank/Indextank/Api.php on line 101