I have a .NET Web Service that works just fine when called form various web pages.
When I call it from an iOS App using Swift I get a 400 Bad Request error, there is no other information in either the event log or HTTP logs on the IIS server to indicate what the issue is.
The IIS FailedRequestLog states:
HttpReason: Bad Request
ErrorCode: The operation completed successfully. (0x0)
The response returned to the app is simply "status code: 400"
How can find out what's "bad"