VS.Net 2005 on Win XP SP2

I'm trying to add a web reference to an external SOAP application written in
RemObjects, but when I attempt to add the reference I get an error message
saying "The proxy settings on this computer are not configured correctly for
web discovery. Press F1 for more information". I am not using a proxy server
or behind a firewall. Other people are able to access the service (from
tools other than VS.Net), but I am not. However, I was able to access it
briefly last week, but now cannot again. I am able to create a web reference
to some other services, such as this:

https://adwords.google.com/api/adwords/v2/CampaignService?wsdl

The one I'm trying to connect to is in this format:

http://myservice.mydomain.com/project/something.dll/soap

One of the common remedies touted for this problem is to uncomment this line
in machine.config:

  <!--<add verb="*" path="*.vsdisco"
type="System.Web.Services.Discovery.DiscoveryRequestHandler,
System.Web.Services, Version=1.0.3300.0, Culture=neutral,
PublicKeyToken=b03f5f7f11d50a3a" validate="false"/>-->

However, I do not have that line. If I were to add it, under what section
would it go? Since I am able to add a reference to some sites, and
occasionally to the target site, I presume this is not the issue.

Any thoughts? TIA!