Setting HTTP Headers
If you need further control over the HTTP headers sent by a web client, you can use the following methods of %SOAP.WebClientOpens in a new tab:
Adds a header to the HTTP request. Note that the Content-Type, Content-Encoding, and Content-Length headers are part of the entity body rather than the HTTP main headers. You cannot set the Content-Length header, which is read-only. Nor can you set the Connection header, because this class does not support persistent connections.
Clear all HTTP headers.
Also see Using HTTP User Authentication.