Thread:Talk:MediaWiki/LocalSettings.php not readable. Please correct file permissions and try again.

I am running Mediawiki on a windows 2008 Server and sometime I receive the following error messageː

After a reload of the page the message disappears and the page is loaded correctly. It appear not at special Wiki page and I haven't found when exactly the error message is displayed.

Anyone have an idea why it appears and how I can fix this problem.

Thank you in advance

Michael