This function posts content to the specified URL. This function only works with HTTP on port 80 and HTTPS on port 443. Non-standard port assignments cause this function to fail. The Marketing Cloud honors any character set returned in the HTTP headers via Content-Type. For example, you can use a UTF-8 encoded HTML file with Content-Type: text/html; charset=utf-8 included in the header. If the header does not specify encoding, the application assumes all returned data will uses the character set WindowsCodePage 1252. You can change this default by contacting your Marketing Cloud account representative. Include as many header name and value pairs as necessary.

HTTPPost(1, 2, 3, 4, 5, 6)

1stringRequiredURL to receive posted content
2stringRequiredSpecified content-type header value
3stringRequiredContent to post to specified URL
4stringRequiredOutput parameter used to contain string representation for the status of the HTTP request, such as OK
5stringName of additional headers to add to HTTP POST request
6stringValue of additional headers to add to HTTP POST request

The system returns the HTTP status code to the specified variable.