Problem with setting up IIS - You are not authorized to view this page

I am trying to set up IIS on our server (Windows 2003 with SQL Server 2000) and when I try to run a query in a browser I keep getting the following messsage:-
You are not authorized to view this page
I have followed the tutorial (XMLStartup.doc) which was placed in C:\Program Files\Microsoft SQL Server\80\Tools\DevTools\Samples\xml\XMLStartup on installation, but still get the above message when I get to the point of querying the database.
Is there something I am doing wrong or is there some security measure I have not taken into account yet that is preventing me from runing queries?
any help appreciated - Thanks
The problem is probably not in SQL Server but in NTFS and IIS permissions. The IUSR_<server name> user or your local account user (if you are surfing from the server) must have NTFS permissions to read the page you are trying to access, both in IIS and NTFS. Check the NTFS security first and disable "simple file sharing" in WinExplorer if it's by any chance turned on and set the propper permissions on the files you are trying to access.