chownpublichtmls while a useful command will not solve this problem if I'm correct.
The message you mention comes from apache and means that there is no index file in that directory (ie public_html probably), and that 'Options -Indexes' is set (rather than 'Options Indexes'). The fix is to place an index file in there, ie restore the site files from elsewhere correctly, or create an index.htm/index.html/index.php file; or, in the unlikely event that you need it to work this way, edit .htaccess to enable the default indexing ('Options Indexes' - but don't do this, as this weakens security, and the fix is probably to restore the site files correctly).