I moved my WP subdir multisite from V3 to V4 and i got this issue when i try to add new posts:
/var/www/htdocs/wp-includes/ – this folder does not exist! It was a setup from EE v3, but now the path to WP is alot different. So my guess is that this is causing the issue but i dont know how and where to fix it.
I can edit old posts just fine. I also cannot add new medias.
Also… i get this error on the main site + a couple of child sites, BUT everything works fine on a couple of other child sites.
The process of movement was… i installed EE v4 on a new server, copied the wp-content from the v3 server and i dumped the database through Mysql and switched DNS. Did i miss something?
Anyone got any ideas?