IMapServer.DefaultMapName throws error

[ShawnHolyoak]

I'm trying to use a web service in a desktop addin, and I'm trying to get access to the data in that web service. When I try to get the MapName string to call GetServerInfo, an exception occurs. The exception is "An event was unable to invoke any of the subscribers". I'm using ArcGIS 10.2.1 with .Net 4. Any ideas on how to get around this?

[ShawnHolyoak]

Just FYI, I've tried it with web services from a 10.2.1 web server and a 10.2.2 web server. The 10.2.1 web server works properly. It seems to be a difference between the web services, but I can't think of anything that would cause this behavior.