problem after installation

[yossimeiri]

Hi,

i just install the Generator folder in im site FTP.
just like in this instractions- http://www.xml-sitemaps.com/howto-install.html
and i cant do the last part - [external links are visible to admins only]

i get this in the page - Directory Listing Denied
This Virtual Directory does not allow contents to be listed.

how can i fix it ?
do i need to do anythink after the installation ?
or just to give to the google webmaster tool the link to the sitemap.xml ?

thank you

[XML-Sitemaps Support]

Please append "index.php" to URL: www.domain.com/generator/index.php