Set default owner/user
Solution 1:
This was fixed by the user by setting the following file permissions using Webmin:
- New Unix file mode: 664
- New Unix directory mode: 775
- Force Unix user: www-data
- Force Unix group: www-data
- Allow symlinks outside share?: Yes [questionable]
- Can delete readonly files?: No
- Force Unix file mode: 000
- Force Unix directory mode: 000
See:
Solution 2:
You can fire up a terminal and type:
sudo chown -R www-data /var/www
The -R stands for recursive for every file and directory under /var/www and www-data will be the owner.