SharePoint

If you’re having some of the following symptoms:
1. You’ve created a web application and you’re sure that credentials are right, but you’re unable to login to the site collection in that web application.
2. Search index log returns strange errors about not finding the web application or access denied.
Then the solution is in the following [...]

Plain simple:
Download: http://technet.microsoft.com/sl-si/evalcenter/ee388573(en-us).aspx
System requirements: http://technet.microsoft.com/en-us/library/cc262485(office.14).aspx