Hi, I am new bie to IIS ,actually i am working as an SQLSERVER DBA,now i want to learn BI concepts thats what i need some easy way to understand IIS,IIS5.0,6.0.................... i need some troubleshooting scenarios and how to resolve?

Dear Friends, I am getting this error " HTTP Error 401.1 - Unauthorized: Access is denied due to invalid credentials. " after the installation of sp2, before that the site was working fine.Please help me out. Rgds Dharmbir