This is an installation issue, so please refer to the big red text box on the New Ticket page; moreover, this is an issue with a plugin, and should therefore be asked to the plugin maintainer - the web site is down for now, but you can still ask your issue on the MailingList, which is where any installation question should be asked anyway.
The error message tells you that the trac.ini file cannot be accessed, so it is likely that your web server does not have read/write permissions on this file or/and the conf directory.
Please act fair with the severity field: an installation issue is not a critical issue.
