I've an account in Digitalocean, they gave me my droplet's IP address and I have a lot of proyects separated in folders, mainly wordpress, prestashop and html.
ls -l www/
drwxrwxr-x 5 www-data www-data 4096 sep 17 12:36 mainwordpress
drwxr-xr-x 20 www-data www-data 4096 may 7 2015 anotherwordpress
drwxrwxr-x 6 www-data www-data 4096 sep 17 13:21 lastwordpress
drwxr-xr-x 6 www-data www-data 4096 ago 11 2015 prestashop
drwxr-xr-x 6 www-data www-data 4096 abr 1 2015 html
The default name-based vhost for an IP and port combination If no matching ServerName or ServerAlias is found in the set of virtual hosts containing the most specific matching IP address and port combination, then the first listed virtual host that matches that will be used.
Your problem is most likely the order of your virtual hosts. Unless you specify the IP address in the
ServerAlias directive it uses the first virtual host as the default host if navigating from the server IP. So however your setup is, apache is reading your mainwordpress vhost first.
You can change the order and make html first or try adding the server ip to the
ServerAlias directive on the html vhost.
Then restart Apache.