XAMPP httpd.conf 127.0.0.1 but no localhost

In httpd.conf I add this:
<Directory />
      Options FollowSymLinks
      AllowOverride None
      Order deny,allow
      Deny from all
      Allow from localhost 127.0.0.1
</Directory>

So dropbox can sync htdocs.

Problem is I have to use 127.0.0.1 in the browser to view my websites i.e. I cannot use localhost. Maybe not resolving machine readable address or can I add this human readable address to the httpd.conf file - what is the syntax please?

Tried this but no luck:
<Directory />
      Options FollowSymLinks
      AllowOverride None
      Order deny,allow
      Deny from all
      Allow from localhost 127.0.0.1
</Directory>

Cheers