If while developing an Indigo Service and browsing to the svc file you are getting an "Server Application Unavailable" error, check the event log of your computer. If you see there 1 warning and one error that goes something like:
"Exception: System.IO.FileLoadException
Message: Could not load file or assembly 'System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a' or one of its dependencies. Access is denied."
Try the following:
Check where you are developing the Indigo service. If it's in you’re my Document folder, just move it to any other place in your computer. It should fix the problem.