I am trying to check if a port is open using the internet site ismyportopen.com, i seem to get to the function HttpOpenRequest working with this get request...

g_hHttpRequest = HttpOpenRequest(g_hNetSession, "GET //processors/port-check.php?ip=xxx.xx.x.xxx&port=80&t=1406357001803" , "", "HTTP/1.1", "", NULL, INTERNET_FLAG_KEEP_CONNECTION, 0);
if(g_hHttpRequest == NULL)
printf("HttpOpenRequest() returned NULL %d\n",GetLastError());

GetlastError returns
ERROR_INVALID_PARAMETER
87 (0x57)
The parameter is incorrect.

the string was captured with a chrome http logger so i dont know how its giving me an error..