getting error 12007 from httpSendRequest ApI function

[Mishi Abolghasem]

I'm trying to use this sequence of VB-API calls to post to a web-page where
client certificate is required.(
InternetOpen,In ternetConnect,H ttpOpenRequest, HttpSendRequest ) And then
InternetReadFil e to save Page on local machine.

InternetConnect works fine with URL which are not protected by digital
certificate and Password, but when I try to access a URL where Digital
certificate and UserId and Password is required it gives me problem.
When I do HttpSendRequest , it returns Err.LastDllErro r=12007(Server name
could not be resolved)
Digital certificate is provided by server admin on my machine.

Here is the code I'm using:

hOpen = InternetOpen("h ttpGetFile", INTERNET_OPEN_T YPE_PRECONFIG,
vbNullString, vbNullString, 0)
hConnect = InternetConnect (hOpen, sUrl, INTERNET_DEFAUL T_HTTPS_PORT, sUID,
sPWD, INTERNET_SERVIC E_HTTP, 0, 0)
hRequest = HttpOpenRequest (hConnect, "post", sURL1, "HTTP/1.0",
vbNullString, vbNullString, INTERNET_FLAG_S ECURE, 0)
bRes = HttpSendRequest (hRequest, vbNullString, 0, "mystirng", 0)

does any body know the problem?
thanks
Mishi