[Owncloud] What to do about this message re data/file security

[Chris Green]

When I go to my owncloud configuration I get the following message at he
top of the page:-

    Your data directory and your files are probably accessible from the
    internet. The .htaccess file that ownCloud provides is not working. We
    strongly suggest that you configure your webserver in a way that the
    data directory is no longer accessible or you move the data directory
    outside the webserver document root. 

Firstly I don't understand why the Owncloud .htaccess file isn't working
as I have lots of other .htacces files which work fine.

Secondly what/where are "your data directory and your files"?  Without
knowing what is meant it's rather difficult to do anything about it!

-- 
Chris Green