I have a simple web service call, generated by a .NET (C#) 2.0 Windows app, via the web service proxy generated by Visual Studio, for a web service also written in C# (2.0). This has worked for several years, and continues to do so at the dozen or so places where it is running.
A new installation at a new site is running into a problem. When attempting to invoke the web service, it fails with the message saying:
Could not establish a trust relationship for the SSL/TLS secure
channel
The URL of the web service uses SSL (https://) — but this has been working for a long time (and continues to do so) from many other locations.
Where do I look? Could this be a security issue between Windows and .NET that is unique to this install? If so, where do I set up trust relationships? I’m lost!