401 Error on Windows 2003 Server Accessing Web Service

[Stephen]

Hi.

I have a web service running on 2003 Server.

The client app running on the same machine gets a 401 error, but
browsing the web service in IE poses no difficulty - even on other
machines.

The virtual directory the web service runs under allows anon access
and runs as the ASPNET user. This is so the web service can write to
the event log without me having to raise the permissions on the IUSR
account.

The web site is running as the NETWORK SERVICE.

Impersonation is on in the web.config.

If I use the IUSR account there is no problem with access but the
event log is untouchable.

Not sure what to do about this.

Any suggestions?

Help appreciated.

 

[Stephen]

Me again.

The problem was the omission of the following in the web.config

<system.web>
<authentication mode="None"/>
</system.web>

I have never needed to use this before on web services so I guess this
might be a security feature of 2003 server.

Thanks to all who looked.