Issue in consuming web service hosted on webmethods

Hi,
we are facing an issue consuming webservice hosted on webmethods server.
We are sending text data to the web service url as https://
using Msxml2.ServerXMLHTTP.6.0 in VB .
When service is on http it works fine but when it changed to https it gives error “A securty error occured”
bellow is a code snap
Set lobjXMLHTTPObj = CreateObject(“Msxml2.ServerXMLHTTP.6.0”)

lstrREQMessage = pstrtextData

lstrURL = “https://myserviceurl…”

lobjXMLHTTPObj.Open “POST”, lstrURL, False

lobjXMLHTTPObj.Send lstrREQMessage

Thanks
Madhukar