I have done a fresh setup of the latest version on 2008 r2 and have the static option installed as I seen this was a common problem.
I get this in the log when trying to login...
Roles: xxxx\Domain Users, Everyone, Veeam Reporter Administrators, Veeam Reporter Viewers,
url=/Welcome.aspx, status = 302 Found,
url=/Reporter/Reporter.aspx, status = 401 Unauthorized,
Is there some other IIS setting that is not getting set right by the installer?
I didn't seem to find anyone else reporting this issue.