HTTP Post from Excel VBA RingCentral FaxoutAPI - vba

Question

I need help getting this code to work. I'm completely new at programming in VBA as well as anything related to HTTP Post and forms. I've tried to do everything to make it work by reading questions here and following the API help but nothing seems to work.
Here is the website where you can find the API Reference:
http://service.ringcentral.com/faxoutapi/
Also here is the code I have so far:
Sub POST()
Dim WinHttpReq As Object
Set WinHttpReq = CreateObject("WinHttp.WinHttpRequest.5.1")
Dim strURL As String
Dim PostData As String
strURL = "https://service.ringcentral.com/faxapi.asp"
Const Boundary As String = "---------------------------7d54b1fee05aa"
WinHttpReq.Open "POST", strURL, False
WinHttpReq.setRequestHeader "Content-Type", "multipart/form-data; boundary=" & Boundary
PostData = "--" & Boundary & vbCrLf
PostData = PostData & "Content-Disposition: form-data; name=""Username""" & vbCrLf
PostData = PostData & "username" & vbCrLf
PostData = PostData & "--" & Boundary & vbCrLf
PostData = PostData & "Content-Disposition: form-data; name=""Password""" & vbCrLf
PostData = PostData & "password" & vbCrLf
PostData = PostData & "--" & Boundary & vbCrLf
PostData = PostData & "Content-Disposition: form-data; name=""Recipient""" & vbCrLf
PostData = PostData & "faxnumber" & vbCrLf
PostData = PostData & "--" & Boundary & vbCrLf
PostData = PostData & "Content-Disposition: form-data; name=""Coverpagetext""" & vbCrLf
PostData = PostData & "This is a test fax from web" & vbCrLf
PostData = PostData & "--" & Boundary & vbCrLf
WinHttpReq.Send (PostData)
MsgBox WinHttpReq.ResponseText
End Sub
I keep getting a response value of 5 which means a generic error. I'm pretty sure the form doesn't match the correct format. I would also like to be able to upload a file as shown in the API's reference.
Thanks in advance

Answer 1

The FaxOut.asp API endpoint was end-of-lifed on August 9 2018.
See more in the noticed here:
https://support.ringcentral.com/article/Legacy-API-End-of-Life-Announcement-RingOut-asp-FaxOut-asp.html
Use the new endpoint at:
https://platform.devtest.ringcentral.com/restapi/v1.0/account/{accountId}/extension/{extensionId}/fax
https://developers.ringcentral.com/api-reference/Fax/createFaxMessage