standalone extplorer webdav does not work with PHP7
webdav use the mysql_connect function wich is no longer available in PHP 7 !
#1 Updated by Daniel Roche about 4 years ago
i have modified libraries/HTTP/WebDAV/Server/Filesystem.php to use mysqli extension rather than mysql.
I usually use PDO for mysql, but i was much easier/faster to use mysqli in this case.
i ran some test, it seems to work correctly on PHP 7 !
you will find the modified file attached, it may help.