HELP - my virtual directory is not working!

When I follow carefully the instruction inside the book,
I cannot access my virtual directory through url query
(404 page not found error). I am sure that I have allowed
the virtual directory to be queried through url. No
matter where I create the actual path to my virtual
directory, I still got error.
Before setting up the virtual directory, I can access the
files in C:\Inetpub\wwwroot\mydb through url, but after
setting up the virtual directory, what I can get is only
404 error. Could anyone help'What I typed is:
http://myservername/mydb?
sql=select+*+from+tablename+for+xml+uto+root=ROOT
I've got a file named index.htm in
C:\Inetpub\wwwroot\mydb, before settting it as virtual
directory, it works, but after, no luck
>--Original Message--
>When I follow carefully the instruction inside the book,
>I cannot access my virtual directory through url query
>(404 page not found error). I am sure that I have
allowed
>the virtual directory to be queried through url. No
>matter where I create the actual path to my virtual
>directory, I still got error.
>Before setting up the virtual directory, I can access
the
>files in C:\Inetpub\wwwroot\mydb through url, but after
>setting up the virtual directory, what I can get is only
>404 error. Could anyone help'
>.
>