I am also having trouble with CreateConfig() and ASP.NET web services.
When I run my code as a standalone application everything works fine and my tags are created in the PI Server. But when I run it as a web service (.NET 4, IIS 7) I have an exception on "DataReference.CreateConfig();":
System.Runtime.InteropServices.COMException: Unable to open a session on a server. [-10431] Authentication method is disabled by current server policy at OSIsoft.AF.Asset.DataReference.PIBaseDR.InFailedServerList(String piServerName, Boolean throwException) at OSIsoft.AF.Asset.DataReference.PIBaseDR.GetPIServer(String piServerName) at OSIsoft.AF.Asset.DataReference.PIBaseDR.GetPIServer() at OSIsoft.AF.Asset.DataReference.PIPointDR.CreateConfig()
My web service is configured to use Integrated Windows Auth and correct Physical Path Credentials.
All AF elements and attributes are created successfully.