( ! ) Fatal error: Uncaught TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "" not found or invalid function name in D:\wamp64\www\tuneposten\wp-includes\class-wp-hook.php on line 326
( ! ) TypeError: call_user_func_array(): Argument #1 ($callback) must be a valid callback, function "" not found or invalid function name in D:\wamp64\www\tuneposten\wp-includes\class-wp-hook.php on line 326
Call Stack
#	Time	Memory	Function	Location
1	0.0002	361552	{main}( )	...\index.php:0
2	0.0003	362744	require( 'D:\wamp64\www\tuneposten\wp-blog-header.php )	...\index.php:17
3	0.6909	80863928	wp( $query_vars = ??? )	...\wp-blog-header.php:16
4	0.6909	80863960	WP->main( $query_args = '' )	...\functions.php:1342
5	0.6912	80898320	WP->query_posts( )	...\class-wp.php:821
6	0.6912	80898376	WP_Query->query( $query = ['category_name' => 'tune', 'feed' => 'feed'] )	...\class-wp.php:701
7	0.6912	80963912	WP_Query->get_posts( )	...\class-wp-query.php:3949
8	0.6922	80978960	get_option( $option = 'posts_per_rss', $default_value = ??? )	...\class-wp-query.php:2030
9	0.6922	80979016	apply_filters( $hook_name = 'pre_option_posts_per_rss', $value = FALSE, ...$args = variadic('posts_per_rss', FALSE) )	...\option.php:132
10	0.6922	80979424	WP_Hook->apply_filters( $value = FALSE, $args = [0 => FALSE, 1 => 'posts_per_rss', 2 => FALSE] )	...\plugin.php:205