While configuring Reporting Services on a server running Windows 2008 R2, I came across this issue. After some searching I found out Microsoft has a kb article about this (http://support.microsoft.com/kb/972328), however it mentions only applying to MSSQL 2005. Well the Server I had had MSSQL 2008 R2, as well as SharePoint 2010 and Exchange 2010. It seems that this fix also still works. So if you are confused as to why this is happening and think the article doesn’t apply to you, give it a shot anyways.