Unable to write config file 'include/config.inc.php'

[tuttosulgsm]

I can't install because exit this message:

The following errors were encountered and need to be corrected first:

Unable to write config file 'include/config.inc.php'


What does it means?
Thank You
Alex

[Nibbler]

http://coppermine-gallery.net/demo/cpg14x/docs/index.htm#permissions