Internet Authentication Service (IAS) does not install.

Hi All,

Currently Im running Windows Server 2003 x32 with WINS, and AD installed. I’m trying to install Internet Authentication Server through Add/Remove Programs. The install stops a 50% and an error message appears saying “could not install Internet Authentication Service component because a file or registry entry is missing”. The Windows Server 2003 CD1 is inserted but it does not prompt for a CD. Has anyone seen this problem before? or know a fix.