There's a problem that's been making my rip my hair out for weeks.

We are trying to set-up a simple subdomain for an add-on domain name.

It is to go to a folder within the main domain. So subdomain.secondomain.com is going to www.maindomain.com/afolder

It doesn't work. Just get a "The page cannot be displayed" error.

We were told by our web host that the .htaccess for the main domain name is stopping the subdomain name from working.

The .htaccess in the root folder is:

Code:
AddHandler server-parsed .html
Options +FollowSymLinks
RewriteEngine on 
RewriteCond %{REQUEST_FILENAME} .*jpg$¦.*gif$ [NC]
RewriteCond %{HTTP_REFERER}!^$ 
RewriteCond %{HTTP_REFERER}!/localhost/ [NC] 
RewriteCond %{HTTP_REFERER}!google\. [NC] 
RewriteCond %{HTTP_REFERER}!search\?q=cache [NC]
# Edit the line below to match your domain name
RewriteCond %{HTTP_REFERER}!domain\.co\.uk [NC]
What can we do to make this .htaccess file not apply to one of the internal folders?

Many many thanks.