I have 401 Error when I try to invoke an ASP Web Service through a client if
Windows Authentication is used.
To identify the reason, I built a simple "Hellow World" Web Service that I
can successfully invoke using IE (regardless of the authentication type
configured in IIS).
I can invoke the same Web Service by another client successfully if the
authentication type is Anonymous (regardless of the actual user who it runs
However, if the Integrated Windows Authentication is ticked, invoking the
service fails (even for the users configured for Anonymous access).
I tried it on XP ...