Thread:Project:Support desk/Mediawiki is not working in Private mode

Hi All, I am trying to setup internal mediawiki for office use, when I make it as Private wiki I get HTTP 500 error, when I make it open wiki it just works fine, I want to setup a private wiki with LDAP authentication, I can work on LDAP part later, but I think I have to get the wiki working in private mode first. I am using, Mediawiki 1.22 IIS 7.5 PHP 5.4 MYSql 5.5