I have created an AFDataReference plugin that used .Net HttpClient to get data from a REST service setup with Windows authentication hosted in IIS. The HttpClient is setup using default credentials.
If I an attribute using the plugin and I get the data in PI System Explorer it works correctly and the REST service is accessed using the user that is running System Explorer.
If I try to get the value for the attribute through the Web API I get a 401 access denied and in the IIS logs there is no user listed. I would expect to find the service account setup to run the Web API.
Why is the running user not sent when doing web request from within the Web API?