If you just installed SQL Server Reporting Services and you are getting a 401.1 Unauthorized error when you try to go to the http://localhost/reports this post may help.  I ran into this and was having a heck of a time figuring it out, since I assumed that since my Reporting Services Configuration Tool was all GREEN that I was good to ...

I spent quite a few hours yesterday trying to get Reporting Services to work on my Vista laptop.  It didn’t end up working.  For quite a long time I got a login prompt when trying to go to localhost/reports, which would bomb after 3 tries and had references to several KB articles, including this ...