"Cannot redeclare get_available_post_mime_types()" appears in the background of WordPress

Here is a record of a problem with a netizen's WordPress website. The front end can be opened, but the error "Fatal error: Cannot redeclare get_available_post_mime_types()" (previously declared in/www/wwwroot/www. * *. com/wp includes/post. php: 7516) in
/Www/wwwroot/www. * * *. com/wp admin/includes/post.php on line 1087 ". When Laojiang asked him what he did, he told him that he was learning an article on the Internet and then modifying the function. Here he was repairing the contents of the wp admin folder.

It is not clear which file he modified here, so I consider directly replacing his core WP file. For example, I directly delete the wp includes and wp admin folders, and then upload the two folders in the latest WP.

Similar to our upgrade of WordPress articles. This can solve the problem.

Source: Lao Jiang Tribe » "Cannot redeclare get_available_post_mime_types()" appears in the background of WordPress |Welcome to share (public account: Chiang's circle of friends)